The solubility of Ba(OH)2 is expected to be ___ in a solution of BaNO3 than in pure water. This is because the BaNO3 solution contains ___ that ___ further dissociation of Ba(OH)2 into Ba^2+ and OH^-. Hint: Consider LeChatelier's principle. A. Equal / Higher / Lower
B. lower pH / barium ions / nitrate ions
C. promote / maintain / inhibit

Answers

Answer 1

LeChatelier's principle states that if a system at equilibrium is subjected to a change, the system will adjust itself to partially counteract the effect of the change. In this case, the addition of BaNO3 to the solution will increase the concentration of Ba^2+ ions in the solution. As a result, according to LeChatelier's principle, the equilibrium will shift towards the left, opposing the increase in Ba^2+ ions, which means that less Ba(OH)2 will dissolve in the BaNO3 solution compared to pure water.

Therefore, the solubility of Ba(OH)2 is expected to be lower in a solution of BaNO3 than in pure water. This is because the BaNO3 solution contains barium ions that promote further dissociation of Ba(OH)2 into Ba^2+ and OH^- ions. Therefore, the Ba^2+ ions in the BaNO3 solution will react with the OH^- ions produced by the dissociation of Ba(OH)2, forming Ba(OH)2(s), which will decrease the solubility of Ba(OH)2.

In summary, the solubility of Ba(OH)2 is expected to be lower in a solution of BaNO3 than in pure water due to the barium ions that promote the formation of the insoluble Ba(OH)2.

To know more about equilibrium visit -

brainly.com/question/30807709

#SPJ11


Related Questions

Consider the following reaction between oxides of nitrogen: NO2(g)+N2O(g)?3NO(g)
Part A
Use data in Appendix C in the textbook to predict how ?G? for the reaction varies with increasing temperature.

Answers

The reaction is spontaneous at all temperatures, so ?G? decreases as temperature increases.

Appendix C provides standard free energy of formation values for various compounds at 298 K. Using these values, we can calculate the standard free energy change (?G°) for the reaction at 298 K. The value of ?G° is negative, indicating that the reaction is spontaneous under standard conditions. Since ?G° is negative, ?G will decrease with increasing temperature according to the equation ?G = ?H - T?S. As the temperature increases, the positive T?S term becomes more dominant, causing ?G to decrease. Therefore, the reaction remains spontaneous at all temperatures, and ?G becomes more negative as the temperature increases.

Learn more about reaction here:

https://brainly.com/question/28984750

#SPJ11

how many milliliters of an 15m hydrogen peroxide solution is required to prepare 250ml of 0.85m solution?

Answers

To calculate the required milliliters of 15m hydrogen peroxide solution, we need to use the formula:
M1V1 = M2V2
Where M1 is the initial concentration, V1 is the initial volume, M2 is the final concentration, and V2 is the final volume.
Substituting the given values, we get:
15m x V1 = 0.85m x 250ml
V1 = (0.85m x 250ml) / 15m



Therefore, 14.17ml of a 15m hydrogen peroxide solution is required to prepare 250ml of 0.85m solution.
To find out how many milliliters of a 15M hydrogen peroxide solution are required to prepare 250mL of a 0.85M solution, you can use the dilution formula:
M1V1 = M2V2
Where M1 and V1 represent the initial molarity and volume, and M2 and V2 represent the final molarity and volume. In this case, M1 is 15M, M2 is 0.85M, and V2 is 250mL. You need to find V1.

Rearranging the formula to solve for V1:
V1 = (M2V2) / M1
Now, plug in the values:
V1 = (0.85M * 250mL) / 15M
V1 = (212.5) / 15
V1 ≈ 14.17mL
So, approximately 14.17 milliliters of a 15M hydrogen peroxide solution are required to prepare 250mL of a 0.85M solution.

To know more about Hydrogen Peroxide visit-

https://brainly.com/question/29102186

#SPJ11

Calculate the pH for each of the following cases in the titration of 35.0 mL of 0.220 M LiOH(aq), with 0.220 M HCl(aq). (a) before addition of any HCl (b) after addition of 13.5 mL of HCl (c) after addition of 25.5 mL of HCl (d) after the addition of 35.0 mL of HCl (e) after the addition of 40.5 mL of HCl (f) after the addition of 50.0 mL of HCl

Answers

The pH after the addition of 50.0 mL of HCl is 0.89.

The reaction between LiOH and HCl is:

LiOH(aq) + HCl(aq) → LiCl(aq) + [tex]H_2O[/tex](l)

Before any HCl is added, the solution contains only LiOH. Therefore, the initial concentration of hydroxide ions [OH-] is:

[OH-] = 0.220 mol/L

(a) Before any HCl is added:

In this case, the solution is a strong base, and the pH can be calculated using the equation:

pH = 14 - pOH

pH = 14 - log([OH-]) = 14 - log(0.220) = 11.66

(b) After addition of 13.5 mL of HCl:

The moles of HCl added is:

moles of HCl = (0.220 mol/L)(0.0135 L) = 0.00297 mol

After the addition of HCl, the total volume of the solution is:

V = 35.0 mL + 13.5 mL = 48.5 mL = 0.0485 L

The moles of LiOH remaining is:

moles of LiOH = (0.220 mol/L)(0.0350 L) = 0.00770 mol

The moles of OH- remaining is:

moles of OH- = 0.00770 mol - 0.00297 mol = 0.00473 mol

The concentration of OH- ions is:

[OH-] = moles of OH-/V = 0.00473 mol/0.0485 L = 0.0975 mol/L

The pOH is:

pOH = -log[OH-] = -log(0.0975) = 1.01

The pH is:

pH = 14 - pOH = 14 - 1.01 = 12.99

(c) After addition of 25.5 mL of HCl:

The moles of HCl added is:

moles of HCl = (0.220 mol/L)(0.0255 L) = 0.00561 mol

After the addition of HCl, the total volume of the solution is:

V = 35.0 mL + 25.5 mL = 60.5 mL = 0.0605 L

The moles of LiOH remaining is:

moles of LiOH = (0.220 mol/L)(0.0350 L) = 0.00770 mol

The moles of OH- remaining is:

moles of OH- = 0.00770 mol - 0.00561 mol = 0.00209 mol

The concentration of OH- ions is:

[OH-] = moles of OH-/V = 0.00209 mol/0.0605 L = 0.0345 mol/L

The pOH is:

pOH = -log[OH-] = -log(0.0345) = 1.46

The pH is:

pH = 14 - pOH = 14 - 1.46 = 12.54

(d) After addition of 35.0 mL of HCl:

The moles of HCl added is:

moles of HCl = (0.220 mol/L)(0.0350 L) = 0.00770 mol

After the addition of HCl, the total volume of the solution is:

V = 35.0 mL + 35.0 mL = 70.0 mL = 0.0700 L

The moles of LiOH remaining is:

moles of LiOH

(f) after the addition of 50.0 mL of HCl:

Before adding any HCl, the solution contains only LiOH, so we can use the Kb of LiOH to calculate the pOH and then convert to pH:

Kb for LiOH = Kw/Ka = 1.0 × 10^-14/2.0 × 10^-11 = 5.0 × 10^-4

pOH = -log(5.0 × 10^-4) = 3.3

pH = 14 - pOH = 10.7

After adding 50.0 mL of HCl, a total of 35.0 + 50.0 = 85.0 mL of solution is present, and the concentration of HCl is:

(0.220 M/L) × (50.0 mL/85.0 mL) = 0.129 M

This is a strong acid, so we can assume complete dissociation and calculate the pH using the concentration of H+:

pH = -log[H+] = -log(0.129) = 0.89

For more question on pH click on

https://brainly.com/question/172153

#SPJ11

LiOH(aq) and HCl(aq) react in a 1:1 molar ratio, meaning that the number of moles of HCl added to the solution is equal to the number of moles of LiOH originally present.

(a) Before the addition of any HCl:

The initial concentration of LiOH is 0.220 M, so the initial concentration of hydroxide ions, [OH-], can be calculated using the following equation:

LiOH → Li+ + OH-

Thus, [OH-] = 0.220 M.

The pOH of the solution can be calculated using the following equation:

pOH = -log[OH-] = -log(0.220) = 0.657

The pH of the solution can be calculated using the following equation:

pH = 14 - pOH = 14 - 0.657 = 13.343

Therefore, the pH of the solution before the addition of any HCl is 13.343.

(b) After the addition of 13.5 mL of HCl:

The amount of HCl added can be calculated using the following equation:

n(HCl) = C(HCl) x V(HCl) = 0.220 M x 0.0135 L = 0.00297 mol

Since HCl and LiOH react in a 1:1 molar ratio, the amount of LiOH remaining in the solution can be calculated as follows:

n(LiOH) = n(LiOH initial) - n(HCl added) = 0.220 M x 0.0350 L - 0.00297 mol = 0.00523 mol

The new volume of the solution is 35.0 mL + 13.5 mL = 48.5 mL.

The new concentration of LiOH can be calculated as follows:

C(LiOH) = n(LiOH) / V(solution) = 0.00523 mol / 0.0485 L = 0.108 M

The new concentration of hydroxide ions can be calculated using the following equation:

LiOH + HCl → LiCl + H2O

The reaction consumes 0.00297 mol of hydroxide ions, so the new concentration of hydroxide ions is:

[OH-] = (0.220 M x 0.0350 L - 0.00297 mol) / 0.0485 L = 0.064 M

The pOH of the solution can be calculated using the following equation:

pOH = -log[OH-] = -log(0.064) = 1.194

The pH of the solution can be calculated using the following equation:

pH = 14 - pOH = 14 - 1.194 = 12.806

Therefore, the pH of the solution after the addition of 13.5 mL of HCl is 12.806.

(c) After the addition of 25.5 mL of HCl:

The amount of HCl added can be calculated using the same equation as before:

n(HCl) = C(HCl) x V(HCl) = 0.220 M x 0.0255 L = 0.00561 mol

The amount of LiOH remaining in the solution can be calculated as follows:

n(LiOH) = n(LiOH initial) - n(HCl added) = 0.220 M x 0.0350 L - 0.00561 mol = 0.00389 mol

The new volume of the solution is 35.0 mL + 25.5 mL = 60.5 mL.

Learn more about LiOH(aq) and HCl(aq) here:

https://brainly.com/question/7082537

#SPJ11

if you start with 1.115 g of aluminum, how many grams of alum should be obtained?

Answers

To calculate the grams of alum that should be obtained from 1.115 g of aluminum, you need to know the balanced chemical equation involving aluminum and alum, as well as the molar masses of the substances involved. Alum is a general term for double sulfates with the formula M2SO4·Al2(SO4)3·24H2O, where M is a monovalent metal (e.g potassium, sodium). Assuming potassium alum (KAl(SO4)2·12H2O) as an example: 2 Al + 2 K2SO4 + 4 H2SO4 + 24 H2O → 2 KAl(SO4)2·12H2O Now, calculate the molar masses: - Aluminum (Al)= 26.98g/mol - Potassium alum (KAl(SO4)2·12H2O): 474.38 g/mol Determine the moles of aluminum: 1.115g Al × (1 mol Al / 26.98g Al) = 0.0413 mol Al Using the stoichiometry of the balanced equation: 0.0413 mol Al × (1 mol KAl(SO4)2·12H2O / 1 mol Al) = 0.0413 mol KAl(SO4)2·12H2O Calculate the grams of potassium alum= 0.0413 mol KAl(SO4)2·12H2O × (474.38 g KAl(SO4)2·12H2O / 1 mol KAl(SO4)2·12H2O) = 19.57 g KAl(SO4)2·12H2O So, if you start with 1.115 g of aluminum, you should obtain approximately 19.57 g of potassium alum. Note that this answer is specific to potassium alum and may vary for other types of alum.

About Aluminum

Aluminum is the most abundant metal. Aluminum is not a heavy metal, but it is an element that accounts for about 8% of the earth's surface and is the third most abundant. An equation is a mathematical statement in the form of a symbol that states that two things are exactly the same. Equations are written with an equal sign, as follows: x + 3 = 5, which states that the value x = 2. 2x + 3 = 5, which states that the value x = 1. The statement above is an equation.

Learn more about aluminum at https://brainly.com/question/246454

#SPJ11

write the net ionic equation for the acid‑base reaction. include physical states. hclo4(aq) koh(aq)⟶h2o(l) kclo4(aq)

Answers

The net ionic equation for the acid-base reaction between perchloric acid (HClO₄) and potassium hydroxide (KOH) is: H⁺(aq) + OH⁻(aq) ⟶ H₂O(l)

The HClO₄ dissociates in water to form H⁺ ions and ClO₄⁻ ions, while KOH dissociates to form K⁺ ions and OH⁻ ions. In the reaction, the H⁺ ion from the acid reacts with the OH⁻ ion from the base to form water.

While the K⁺ ion and ClO₄⁻ ion remain in solution and are spectator ions. Therefore, they are not included in the net ionic equation.

It's worth noting that the perchloric acid (HClO₄) and potassium hydroxide (KOH) are both strong acids and bases, respectively, meaning that they completely dissociate in water.

This makes the reaction a neutralization reaction, which involves the combination of an acid and a base to form water and a salt. In this case, the salt formed is KClO₄.

To know more about perchloric acid, refer here:

https://brainly.com/question/30780596#

#SPJ11

a piece of metal with a mass of 2185 g absorbs 431 j at 23 0c . its temperature changes to 24 oc. what is the specific heat of the metal?

Answers

The specific heat of the metal is 0.196 J/g°C.

To calculate the specific heat of the metal, we can use the formula:

q = m * c * ΔT

Where q is the amount of heat absorbed, m is the mass of the metal, c is the specific heat of the metal, and ΔT is the change in temperature.

In this case, we know that the mass of the metal is 2185 g and the heat absorbed is 431 J. We also know that the initial temperature is 23°C and the final temperature is 24°C.


First, we need to calculate the change in temperature:
ΔT = final temperature - initial temperature
ΔT = 24°C - 23°C
ΔT = 1°C

Now we can plug in the values we know and solve for c:

431 J = 2185 g * c * 1°C
c = 431 J / (2185 g * 1°C)

c = 0.196 J/g°C

Therefore, the specific heat of the metal is 0.196 J/g°C. This means that it takes 0.196 J of energy to raise the temperature of 1 gram of the metal by 1°C.

To know more about specific heat, refer here:

https://brainly.com/question/29766819#

#SPJ11

Show that the initial rate law predicted by the reaction mechanism 6-12a-c, with the first step rate-limiting, is rate = 2k1[Cl2]. Assume that the Cl . produced in step (3) can be neglected initially. Please show step by step calculations and answer it completely Cl2 2Cl (6-12a) cl. + co cICo (6-12b) cico'+ Cl Cl,CO + Cl (6-12c)

Answers

The initial rate law predicted by the reaction mechanism 6-12a-c, with the first step rate-limiting, is rate = 2k₁[Cl₂], where [Cl₂] represents the concentration of Cl₂ and k₁ is the rate constant for the first step.

According to the given mechanism, the reaction proceeds through three steps: 6-12a, 6-12b, and 6-12c. The first step (6-12a) is assumed to be rate-limiting, meaning it is the slowest step and determines the overall rate of the reaction.

In the first step (6-12a), Cl₂ reacts to form two Cl radicals (Cl.). The stoichiometry of this step indicates that for every molecule of Cl₂ consumed, two Cl radicals are produced.

Since the rate of the reaction is determined by the rate of the slowest step (6-12a), the rate law is directly proportional to the concentration of Cl₂. Thus, the rate law can be written as rate = k₁[Cl₂], where k₁ is the rate constant for the first step.

As specified in the question, the rate law is rate = 2k₁[Cl₂] because two moles of Cl radicals are produced per mole of Cl₂ consumed in the first step (6-12a).

Therefore, the initial rate law predicted by the given reaction mechanism is rate = 2k₁[Cl₂].

learn more about rate law here:

https://brainly.com/question/31873163

#SPJ11

Which compound is an alcohol? a. CH3OCH3 b. CH4 c. C2H6 d. C6H5OH e. CH3NH2

Answers

The compound that is an alcohol is option d, C6H5OH. This is because the compound has the -OH functional group, which is the defining feature of alcohols. Option a, CH3OCH3, is a compound called dimethyl ether and is not an alcohol. Option b, CH4, is methane and does not have any functional groups.

Option c, C2H6, is ethane and is also not an alcohol. Option e, CH3NH2, is methylamine and does not have an -OH functional group, so it is also not an alcohol.

The options are a. CH3OCH3, b. CH4, c. C2H6, d. C6H5OH, and e. CH3NH2.

The compound that is an alcohol is d. C6H5OH. Alcohols are organic compounds containing a hydroxyl (-OH) group attached to a carbon atom. In C6H5OH, also known as phenol, the hydroxyl group is bonded to a carbon atom in a benzene ring, fulfilling the criteria of an alcohol. The other compounds are not alcohols: a. CH3OCH3 is an ether, b. CH4 is a hydrocarbon (methane), c. C2H6 is a hydrocarbon (ethane), and e. CH3NH2 is an amine (methylamine).

To know more about Alcohol visit:

https://brainly.com/question/30829120

#SPJ11

Two atoms of cesium (Cs) can form a Cs molecule. The equilibrium distance between the nuclei in a molecule is 0.447 Calculate th…
Two atoms of cesium (Cs) can form a Cs molecule. The equilibrium distance between the nuclei in a molecule is 0.447 Calculate the moment of inertia about an axis through the center of mass of the two nuclei and perpendicular to the line joining them. The mass of a cesium atom is 2.2 .

Answers

The moment of inertia about an axis through the center of mass of the two nuclei and perpendicular to the line joining them is 0.223 kg⋅m².

To calculate the moment of inertia, we need to use the formula:

I = μr²

where I is the moment of inertia, μ is the reduced mass, and r is the distance between the two nuclei.

First, we need to calculate the reduced mass:

μ = m₁m₂ / (m₁ + m₂)

where m₁ and m₂ are the masses of the two Cs atoms.

Since we have two Cs atoms, the mass of each is 2.2, so we have:

μ = (2.2)(2.2) / (2.2 + 2.2) = 1.1

Now we can calculate the moment of inertia:

I = (1.1) (0.447)²

 = 0.223 kg⋅m²

To know more about the moment of inertia, click below.

https://brainly.com/question/15246709

#SPJ11

identify the least stable conformation for 1-tert-butyl-3-methylcyclohexane.

Answers

The least stable conformation for 1-tert-butyl-3-methylcyclohexane would be the twist-boat conformation where the tert-butyl and methyl groups are in axial positions, resulting in the maximum steric hindrance.

1-tert-butyl-3-methylcyclohexane is a cyclohexane ring with a tert-butyl group and a methyl group attached to it. To identify the least stable conformation, we need to consider the steric hindrance between the groups and their orientation.

One method to visualize different conformations is to use Newman projections, which show the molecule from the point of view of looking down the C-C bond.

For example, the Newman projection for 1-tert-butyl-3-methylcyclohexane in its most stable conformation would show the tert-butyl group in an equatorial position and the methyl group in an axial position. This is the most stable conformation because it minimizes the steric hindrance between the groups.

To identify the least stable conformation, we need to find the conformation that maximizes the steric hindrance. In this case, the tert-butyl group and the methyl group should be in axial positions to create the most steric hindrance.

This would result in a twist-boat conformation where the carbon atoms in the ring are no longer coplanar. This conformation is significantly less stable than the most stable conformation, which is a chair conformation, due to the increased steric hindrance.

For more question on conformation visit:

https://brainly.com/question/30579110

#SPJ11

For 6 points, a 0.50 liter solution of 0.10 M HF titrated to the half way point with a 0.10 M solution of NaOH. Determine the pH of the half way point. Use two significant figures in your final answer.

Answers

The pH at the half-way point is 3.17. The equation for the neutralization reaction between HF and NaOH: HF + NaOH -> NaF + H2O

At the half way point, half of the HF has reacted with NaOH, leaving half of it still in solution. This means that the concentration of HF has been reduced by half, so it is now 0.05 M. The reaction between HF and NaOH produces NaF and water, but NaF is a salt that does not affect the pH of the solution. So, we can focus on the remaining HF and the water.
HF + H2O -> H3O+ + F-

To determine the pH of the solution at the half way point, we need to calculate the concentration of H3O+ ions. We can use the equilibrium constant expression for the reaction above:                                                                           Kw = [H3O+][OH-] = 1.0 x 10^-14
moles NaOH = concentration x volume = 0.10 M x 0.25 L = 0.025 mol
Kw = [H3O+][F-] / [HF]
1.0 x 10^-14 = [H3O+][0.05 M / 2] / 0.20 M
Solving for [H3O+] gives:  [H3O+] = 2.5 x 10^-4 M
Finally, we can calculate the pH using the definition of pH:
pH = -log[H3O+] = -log(2.5 x 10^-4) = 3.60
The pH of the solution at the half way point of the titration is 3.60 (rounded to two significant figures).
pH = pKa + log ([A-]/[HA])

The pKa of HF. The Ka of HF is 6.8 x 10^-4, so the pKa is:
pKa = -log(Ka) = -log(6.8 x 10^-4) = 3.17
At the half-way point, [A-] = [HA], so the ratio [A-]/[HA] = 1. The log(1) is 0, so: pH = pKa + log(1) = 3.17 + 0 = 3.17

To know more about neutralization visit:-

https://brainly.com/question/15347368

#SPJ11

What is the molecular formula of a cycloalkane that has six carbon atoms? A. C6H14 B. C6H12 C. C6H16 D. C6H10

Answers

The molecular formula of a cycloalkane with six carbon atoms, also known as cyclohexane, is C6H12.

Cycloalkanes are cyclic hydrocarbons that consist of carbon atoms arranged in a ring, with each carbon atom bonded to two other carbon atoms and two hydrogen atoms. Cycloalkanes are saturated hydrocarbons, meaning that they contain only single covalent bonds between the carbon atoms and hydrogen atoms, and have the general formula CnH2n. Cycloalkanes are relatively stable compounds and can be found in many natural products, such as steroids, and alkaloids. They are also used in various applications, such as solvents, fuels, and lubricants.

Therefore, the correct answer is B. C6H12.

To know more about cycloalkane : https://brainly.com/question/10189586

#SPJ11

consider the molecule cocl2. (cl = chlorine not carbon and iodine) what is the hybridization of the central atom?

Answers

The hybridization of the central atom in COCl₂ is sp³.

The central atom in COCl₂ is carbon, which has four valence electrons. To form the bonds with two chlorine atoms and one oxygen atom, carbon needs to hybridize its orbitals. It combines one s and three p orbitals to form four sp³ hybrid orbitals that are directed towards the corners of a tetrahedron.

The carbon atom then forms a sigma bond with each of the three surrounding atoms using these sp³ hybrid orbitals, while the fourth hybrid orbital contains a lone pair of electrons. This hybridization allows for the geometry of the molecule to be tetrahedral with bond angles of approximately 109.5 degrees.

Hybridization is a concept used to describe the bonding in molecules. It refers to the mixing of atomic orbitals to form new hybrid orbitals that are involved in bonding. In the case of COCl₂ , the central atom is carbon, which has four valence electrons and can form four covalent bonds.

The molecule has a trigonal planar geometry with the chlorine atoms occupying three of the four positions around carbon. This suggests that the carbon atom is sp² hybridized, meaning that it has mixed one s orbital and two p orbitals to form three hybrid orbitals. These hybrid orbitals are arranged in a trigonal planar geometry, with 120° angles between them. The remaining p orbital is perpendicular to the plane of the hybrid orbitals and is used to form a pi bond with the oxygen atom.

learn more about   orbitals here:

https://brainly.com/question/31962087

#SPJ11

cyanide is a non-competitive inhibitor of cytochrome c oxidase. what km would you expect if you treated 12µm cytochrome oxidase with enough cyanide to lower the enzymes vmax to 40 units of activity?

Answers

The [tex]K_m[/tex] value would remain at 12 µM after treatment with enough cyanide to lower the enzyme's [tex]V_m_a_x[/tex] to 40 units of activity.

Since cyanide is a non-competitive inhibitor of cytochrome c oxidase, the Km value of the enzyme will remain unchanged after treatment with cyanide. Cyanide is a non-competitive inhibitor of cytochrome c oxidase, which means that it binds to the enzyme at a site other than the active site, and does not directly interfere with substrate binding.

Therefore, we can use the Michaelis-Menten equation to solve for the  [tex]K_m[/tex]value:


[tex]V_m_a_x[/tex] = ([tex]V_m_a_x[/tex] / [tex]K_m[/tex]) [S] +[tex]V_m_a_x[/tex]

Rearranging the equation, we get:

[tex]K_m[/tex] = ([S] ([tex]V_m_a_x[/tex]/40)) - [S]

We know that [S] = 12 µM and [tex]V_m_a_x[/tex] = 40 units of activity. Plugging in these values, we get:

[tex]K_m[/tex] = (12 µM x 40 units of activity/40 units of activity) - 12 µM

[tex]K_m[/tex] = 0 µM

Therefore, the Km value would remain at 12 µM after treatment with enough cyanide to lower the enzyme's [tex]V_m_a_x[/tex] to 40 units of activity.

To know more about enzyme refer here :

https://brainly.com/question/31621283

#SPJ11

For the reaction N 2

(g)+2O 2

(g)→2NO 2

(g)
ΔH ∘
=66.4 kJ and ΔS ∘
=−122 J/K

The equilibrium constant for this reaction at 342.0 K is Assume that ΔH ∘
and ΔS ∘
are independent of temperature.

Answers

The equilibrium constant (K) for this reaction at 342.0 K is approximately 2.3 × 10^(-17).

For the given reaction, N2(g) + 2O2(g) → 2NO2(g), we are provided with ΔH° = 66.4 kJ and ΔS° = -122 J/K. We can calculate the equilibrium constant at 342.0 K using the Van't Hoff equation, which relates the change in Gibbs free energy (ΔG°) to the equilibrium constant (K):
ΔG° = -RTlnK
First, we need to calculate ΔG° using the provided ΔH° and ΔS° values:
ΔG° = ΔH° - TΔS°
Since the given ΔH° is in kJ, we need to convert it to J:
ΔH° = 66.4 kJ * 1000 = 66400 J
Now, we can calculate ΔG° at 342.0 K:
ΔG° = 66400 J - (342.0 K * -122 J/K) = 66400 J + 41724 J = 108124 J
Next, we can find the equilibrium constant (K) using the Van't Hoff equation:
108124 J = -(8.314 J/(mol·K)) * 342.0 K * lnK
Solve for K:
lnK = -108124 J / (8.314 J/(mol·K) * 342.0 K) = -38.3
K = e^(-38.3) ≈ 2.3 × 10^(-17)
Thus, the equilibrium constant (K) for this reaction at 342.0 K is approximately 2.3 × 10^(-17).

To know more about Equilibrium constant visit:

https://brainly.com/question/10038290

#SPJ11

Be sure to answer all parts. What acetylide anion and alkyl chloride can be used to prepare the following alkyne? View stnctute Acetylide Anion view stnucture

Answers

To provide a concise answer, I'll need the specific structure of the alkyne you are referring to. However, in general, to prepare an alkyne using an acetylide anion and an alkyl chloride, follow these steps:

To prepare the alkyne shown in the provided structure, we need to use a specific acetylide anion and alkyl chloride. The acetylide anion that we need to use is ethynide anion, which has the structure shown in the provided image. The alkyl chloride that we need to use is 1-bromo-2-chloropropane, which has the structure shown below:


In summary, to prepare the alkyne shown in the provided structure, we need to use ethynide anion and 1-bromo-2-chloropropane in a nucleophilic substitution reaction.

To know more about alkyne visit :-

https://brainly.com/question/9620187

#SPJ11

A statistics professor finds that when she schedules an office hour for student help, an average of 1.9 students arrive. Find the probability that in a randomly selected office hour, the number of student arrivals is 7.

Answers

To find the probability that in a randomly selected office hour the number of student arrivals is 7, we can use the Poisson distribution formula.

The Poisson distribution is used to model the probability of a certain number of events occurring within a fixed interval of time or space, given the average rate of occurrence.

In this case, the average number of student arrivals is 1.9.

The probability of exactly k events occurring in a Poisson distribution is given by the formula:

P(X=k) = (e^(-λ) * λ^k) / k!

Where λ is the average rate of occurrence.

Using this formula, we can calculate the probability of exactly 7 student arrivals in the given office hour:

P(X=7) = (e^(-1.9) * 1.9^7) / 7!

Calculating this expression will give us the desired probability.

Note: The value of e in the formula represents the base of the natural logarithm and is approximately equal to 2.71828.

 To  learn  more  about Poisson click here:brainly.com/question/31019106

#SPJ11

Mg(oh)2 has a ksp = 1.2 × 10^-11 . what is the chemical reaction? find the molar solubility of mg(oh)2 .

Answers

The chemical reaction for Mg(OH)2 is: Mg(OH)2 (s) ⇌ Mg2+ (aq) + 2OH- (aq). The molar solubility of Mg(OH)2 is approximately 1.44 × 10^-4 M.

The solubility product constant (Ksp) is an equilibrium constant that relates to the dissolution of a sparingly soluble salt in water. In this problem, we were given the Ksp value for magnesium hydroxide (Mg(OH)2), which is a sparingly soluble salt that partially dissociates into magnesium ions (Mg2+) and hydroxide ions (OH-) in water.
Given the Ksp value of 1.2 × 10^-11, we can determine the molar solubility. Let's denote the molar solubility as "x."
Ksp = [Mg²⁺][OH⁻]^2 Since the stoichiometry is 1:2, the concentration of OH⁻ ions will be twice that of Mg²⁺ ions. Thus, we can express the Ksp in terms of x: 1.2 × 10^-11 = [x][2x]^2 Solve for x to find the molar solubility of Mg(OH)2:
1.2 × 10^-11 = 4x^3
x ≈ 1.44 × 10^-4 M

To know more about solubility visit :-

https://brainly.com/question/30639017

#SPJ11

.46) draw the major product of the following reaction mechanism: Cl2+, H2O
47) draw the major product of the following reaction mechanism: Br2, CH2Cl2
48) draw the major product of the following reaction mechanism not needed: CH3CO3H
49) Draw the product of the following reaction not needed: O3, (CH3)2S

Answers

46) The major product of the reaction mechanism between Cl2+ and H2O is HOCl, which is formed through the reaction Cl2+H2O -> HOCl + H+ + Cl-
47) The major product of the reaction mechanism between Br2 and CH2Cl2 is the addition product of Br2 and CH2Cl2, which is formed through the reaction Br2+CH2Cl2 -> BrCH2Cl + HBr
48) The reaction mechanism not needed for the question, therefore no answer can be given.
49) The product of the following reaction between O3 and (CH3)2S is dimethyl sulfide oxide, which is formed through the reaction O3 + (CH3)2S -> (CH3)2SO + O2.
As a text-based AI, I am unable to physically draw the structures of the products for these reactions. However, I can provide you with a brief description of the major products and their formation.
46) In the presence of Cl2 and H2O, an alkene will undergo halohydrin formation. The major product will be a halohydrin, with the Cl atom attached to the less substituted carbon and an OH group attached to the more substituted carbon of the alkene.
47) When an alkene reacts with Br2 and CH2Cl2, it undergoes a halogenation reaction. The major product will be a vicinal dibromide, with Br atoms added across the double bond of the alkene.
48) When CH3CO3H (peracetic acid) is used as a reagent, it typically results in an epoxidation reaction for an alkene. The major product will be an epoxide, with an oxygen atom inserted into the double bond.
49) When an alkene reacts with O3 followed by (CH3)2S (dimethyl sulfide), it undergoes an ozonolysis reaction. The major product will be two carbonyl compounds formed from the cleavage of the double bond in the alkene.

To know more about alkene visit:

https://brainly.com/question/31033378

#SPJ11

determine the most basic nitrogen in each compound. why?

Answers

The most basic nitrogen in a compound refers to the nitrogen atom with the highest ability to attract and donate a proton (H+), resulting in the formation of a stable conjugate acid. To determine the most basic nitrogen, we need to consider factors such as electron density and resonance effects.

To determine the most basic nitrogen in each compound, we need to look at the chemical structure and identify the nitrogen that is the most likely to accept a proton (H+) and form a positive charge. This nitrogen is called the basic nitrogen.


In a compound with multiple nitrogen atoms, the basic nitrogen is typically the one with the lone pair of electrons that is least hindered by neighboring groups or substituents. This is because the lone pair of electrons on the nitrogen is more accessible to an incoming proton.
A long answer to this question would involve analyzing the structures of different compounds and identifying the basic nitrogen in each one.

To  know more about compound visit :-

https://brainly.com/question/13516179

#SPJ11

Air at 27 °C, 1 atm and a volumetric flow rate of 40 m^3/min enters an insulated control volume operating at steady state and mixes with helium entering as a separate stream at 120 °C, 1 atm and a volumetric flow rate of 25 m^3/min. The mixture exits at 1 atm. Assuem ideal gas behavior, steady-state processes, with ¯M = 28.97, cpair = 1.008 kJ/kg⋅ K, and ¯MHe= 4.003, cpHe = 5.96 kJ/kg⋅K.

Answers

The process is adiabatic since the control volume is insulated, so there is no heat transfer and the temperature change is due to the mixing of the two streams.

When air at 27°C and 1 atm is mixed with helium at 120°C and 1 atm, at a volumetric flow rate of 40 m^3/min and 25 m^3/min respectively, the mixture exits at 1 atm. Assuming ideal gas behavior, steady-state processes, with molar mass and specific heat capacity given, the final temperature of the mixture can be calculated as 49.4K

The problem can be solved using the conservation of mass and energy equations. Since the control volume is insulated, there is no heat transfer. Therefore, the energy equation reduces to the conservation of enthalpy. The mass flow rates of air and helium and their specific heat capacities are given, and the molar mass of the mixture can be calculated from the mole fractions of air and helium. The mole fractions can be calculated using the volumetric flow rates and the molar volumes of air and helium at their respective conditions.

Using the conservation of mass equation, the mole fractions of air and helium in the mixture are found to be 0.783 and 0.217, respectively. Using the conservation of enthalpy equation, the final temperature of the mixture can be calculated as 49.4°C.

Learn more about adiabatic:https://brainly.com/question/28302589

#SPJ11

calculate the molarity of the cesium chloride solution in the previous question if the density of the solution is 1.58 g/ml

Answers

The molarity of the cesium chloride solution is 0.063 M. To calculate the molarity of the cesium chloride solution, we first need to determine the number of moles of cesium chloride present in the solution.

From the previous question, we know that we have 0.050 moles of cesium chloride dissolved in 500 mL of solution.

To convert 500 mL to grams, we multiply by the density of the solution:

500 mL x 1.58 g/mL = 790 g

Now we can use the formula:

Molarity = moles of solute / liters of solution

To find the number of liters of solution, we convert the mass of the solution to liters:

790 g / 1000 g/L = 0.79 L

Now we can plug in our values:

Molarity = 0.050 moles / 0.79 L = 0.063 M

Therefore, the molarity of the cesium chloride solution is 0.063 M.

To know more about molarity, refer

https://brainly.com/question/30404105

#SPJ11

a spring system doing simple harmonic motion has an amplitude of 5.00 cm and a maximum speed of 30.0 cm/s. what is the displacement when its speed is 15.0 cm/s?

Answers

The displacement of the spring system when its speed is 15.0 cm/s is 3.75 cm.

The amplitude (A) of a spring system doing simple harmonic motion is the maximum displacement from the equilibrium position. In this case, the amplitude is given as 5.00 cm.

The maximum speed (v_max) occurs when the displacement is zero, and is equal to the amplitude multiplied by the angular frequency (ω) of the motion:

v_max = Aω

We can rearrange this equation to solve for the angular frequency:

ω = v_max / A

The displacement (x) of the spring system at any given time can be expressed as:

x = Acos(ωt)

where t is the time. To find the displacement when the speed is 15.0 cm/s, we need to first find the corresponding time.

At this speed, the velocity is half of the maximum velocity, so we can set:

15.0 cm/s = (1/2)v_max

Solving for v_max gives:

v_max = 30.0 cm/s

So, we have:

ω = v_max / A = (30.0 cm/s) / (5.00 cm) = 6.00 s⁻¹

Now, we can use the equation for displacement to find x when the velocity is 15.0 cm/s:

x = Acos(ωt)

15.0 cm/s = -Aωsin(ωt)

sin(ωt) = -(15.0 cm/s) / (Aω) = -0.50

At this point, we can use a calculator to find the value of the angle (ωt) that gives a sin of -0.50, which is approximately 30°.

Since we know that the displacement is at its maximum when the speed is zero, we can subtract the amplitude multiplied by the cosine of 30° to find the displacement at the given speed:

x = Acos(ωt) - A = (5.00 cm)cos(30°) - (5.00 cm) = 3.75 cm

To know more about spring system, refer here:

https://brainly.com/question/30393799#

#SPJ11

methylamine, ch3nh2, has a kb = 4.40 x 10-4. 1st attempt see hintsee periodic table what is the ph of a 0.360 m solution of methylamine?

Answers

The pH of the 0.360 M solution of the methylamine solution is the 12.

The methylamine solution of chemical equation is as :

CH₃NH₂ + H₂O ==> CH₃NH₃⁺ + OH⁻

The expression for the kb is as :

Kb = [CH₃NH₃⁺ ]  [OH⁻] / [CH₃NH₂ ]

The value of kb for the methylamine =  4.38 x 10⁻⁴

4.38 x 10⁻⁴ = (x)(x) / 0.360 - x

x = 1.14 x 10⁻² M = [OH⁻]

The value of hydroxide ion,   [OH⁻] = 1.14 x 10⁻² M

The expression for the pOH is :

pOH = - log (OH⁻)

pOH = - log ( 1.14 x 10⁻²)

pOH = 1.94

pH = 14 - 1.94

pH = 12

The pH of the methylamine solution is 12 with the 0.360 M.

To learn more about pH here

https://brainly.com/question/2288405

#SPJ4

(A) Calculate (in MeV) the binding energy per nucleon for 56Fe. (B) Calculate (in MeV) the binding energy per nucleon for 207Pb.

Answers

The binding energy per nucleon for 56Fe is 8.802 MeV/nucleon, and the binding energy per nucleon for 207Pb is 7.861 MeV/nucleon.

The mass of a 56Fe nucleus is 55.934941 u, which is equivalent to 931.502 MeV/c² (using E=mc²). Therefore, the total binding energy of the nucleus will be;

B = (56 nucleons) × (8.794 MeV/nucleon) = 492.864 MeV

The binding energy per nucleon is then;

B/A = 492.864 MeV / 56 nucleons

= 8.802 MeV/nucleon

Therefore, the binding energy is 8.802 MeV.

The mass of a 207Pb nucleus is 206.975896 u, which is equivalent to 3,842.943 MeV/c². Therefore, the total binding energy of the nucleus is;

B = (207 nucleons) × (7.870 MeV/nucleon) = 1,627.049 MeV

The binding energy per nucleon is then;

B/A = 1,627.049 MeV / 207 nucleons

= 7.861 MeV/nucleon

Therefore, the binding energy is 7.861 MeV.

To know more about binding energy here

https://brainly.com/question/31745060

#SPJ4

Choose the relationship that is INCORRECT a. Na+ = 1 Atrial Natriuretic Hormone (ANH) b. Na+ = 1 Atrial Natriuretic Hormone (ANH) c. Na+ = 1 Anti-diuretic hormone (ADH) d. Na+ = | Aldosterone (ALDO)

Answers

The relationship that is INCORRECT is Na+ = | Aldosterone (ALDO). So the correct answer is option d.

The relationship is incorrect because aldosterone promotes the reabsorption of sodium ions, not excretion, so it would not be expected to have a 1:1 relationship with Na+.

The correct relationship is Na+ = 1 Atrial Natriuretic Hormone (ANH), which promotes the excretion of sodium ions, and is therefore inversely related to Na+ levels. Na+ = 1 Anti-diuretic hormone (ADH) is also a correct relationship, as ADH regulates water balance in the body and can indirectly affect Na+ levels.

So option d is the correct answer.

To learn more about Atrial Natriuretic Hormone: https://brainly.com/question/9360479

#SPJ11

For a galvanic cell using Fe | Fe2+(0.25 M) and Pb | Pb2+0.25 M) half-cells, which of the following statements is correct?Fe2+(aq)+2e−⇌Fe(s); E = -0.41 VPb2+(aq)+2e−⇌ Pb(s); E = -0.13 Va. The iron electrode is the cathode.b. When the cell has completely discharged, the concentration of Pb2+ is zeroc. The mass of the iron electrode increases during discharge.d. The concentration of Pb2+ decreases during discharge.

Answers

The correct statement for the galvanic cell using Fe | Fe²⁺(0.25 M) and Pb | Pb²⁺(0.25 M) half-cells is:  The iron electrode is the cathode. Option a is correct.

This is because the half-reaction with the higher reduction potential (more positive E value) will occur at the cathode, which in this case is Fe²⁺(aq)+2e−⇌Fe(s); E = -0.41 V. Pb²⁺(aq)+2e−⇌ Pb(s); E = -0.13 V will occur at the anode.
b. When the cell has completely discharged, the concentration of Pb²⁺ is zero.
This is not a correct statement as the concentration of Pb²⁺ will still be present in the half-cell. However, it will be depleted as the cell discharges.
c. The mass of the iron electrode increases during discharge.
This is also not a correct statement as the mass of the iron electrode will decrease as it is oxidized to Fe²⁺.
d. The concentration of Pb²⁺ decreases during discharge.
This is a  statement as Pb²⁺ ions will be reduced to Pb(s) at the Pb electrode during discharge, galvanic cell leading to a decrease in the concentration of Pb²⁺ in the half-cell.

Learn more about galvanic cell here

https://brainly.com/question/13031093

#SPJ11

A nucleus that is small (<20 protons) will have close to this ratio of neutrons to protons (n/p= ?)

Answers

A small nucleus with less than 20 protons will generally have a neutron-to-proton ratio (n/p) close to 1:1, meaning approximately an equal number of neutrons and protons.

The neutron-to-proton ratio in a nucleus is influenced by various factors, including the stability of the nucleus and the balance between the strong nuclear force and electrostatic repulsion. In smaller nuclei with fewer than 20 protons, the n/p ratio tends to be close to 1:1.

The strong nuclear force, which binds protons and neutrons together, plays a crucial role in stabilizing the nucleus. As the number of protons increases, the electrostatic repulsion between the positively charged protons also increases. To counterbalance this repulsion and maintain stability, additional neutrons are needed. In smaller nuclei, the number of protons is relatively low, and a nearly equal number of neutrons can effectively stabilize the nucleus.

It's important to note that this is a general trend and not a strict rule. There can be variations in the neutron-to-proton ratio among different elements and isotopes, even within the category of small nuclei. The specific number of neutrons relative to protons may vary depending on the specific element or isotope under consideration.

Learn more about neutrons here: https://brainly.com/question/31977312

#SPJ11

What is the correct assignment of the names of the following aromatic amines? 1-pyrrolidine; Il = pyrimidine;

Answers

The correct name for the aromatic amine "Il = pyrimidine" is simply "pyrimidine."

Pyrimidine is an aromatic heterocyclic compound, which consists of a six-membered ring with two nitrogen atoms at positions 1 and 3.

Pyrimidine is a six-membered heterocyclic ring structure composed of four carbon atoms and two nitrogen atoms.

The nitrogen atoms are located at positions 1 and 3 within the ring. The aromatic nature of pyrimidine arises from the presence of a conjugated π electron system, which contributes to its stability and unique chemical properties.

Pyrimidine is an essential building block in nucleic acids, where it pairs with purines (adenine and guanine) to form the genetic code in DNA and RNA. It plays a critical role in storing and transmitting genetic information and is involved in various biological processes.

To summarize, pyrimidine is an aromatic heterocyclic compound with a six-membered ring containing two nitrogen atoms. It is not an aromatic amine but rather an important component of nucleic acids.

To learn more about compound, refer below:

https://brainly.com/question/13516179

#SPJ11

when the reaction, cl2(aq) → cl-(aq) clo3-(aq) is balanced in aqueous basic solution, what is the coefficient of h2o?

Answers

To balance the given redox reaction in aqueous basic solution, we follow these steps:

1. Write the unbalanced equation:

Cl2(aq) → Cl^-(aq) + ClO3^-(aq)

2. Identify the oxidation states and the atoms that are undergoing oxidation and reduction:

Cl2 is being reduced to Cl^-, and its oxidation state is changing from 0 to -1. Cl2 is also being oxidized to ClO3^-, and its oxidation state is changing from 0 to +5.

3. Balance the atoms that are not hydrogen or oxygen:

The chlorine atoms are already balanced.

4. Balance oxygen by adding water (H2O) to the side that needs it:

There are 3 oxygen atoms on the right-hand side and only 1 on the left, so we need to add 2 water molecules to the left-hand side to balance the oxygen:

Cl2(aq) + 2H2O(l) → Cl^-(aq) + ClO3^-(aq)

5. Balance hydrogen by adding hydrogen ions (H+) to the opposite side:

There are 4 hydrogen atoms on the right-hand side and none on the left, so we need to add 8 H+ ions to the left-hand side to balance the hydrogen:

Cl2(aq) + 2H2O(l) + 8H+(aq) → Cl^-(aq) + ClO3^-(aq)

6. Balance the charge by adding electrons (e-) to the side that needs it:

The overall charge on the left-hand side is +2 (from the H+ ions), and the overall charge on the right-hand side is -1 (from the Cl^- ion). We need to add 6 electrons to the left-hand side to balance the charge:

Cl2(aq) + 2H2O(l) + 8H+(aq) + 6e^(-) → Cl^-(aq) + ClO3^-(aq)

Now the equation is balanced in aqueous basic solution, and there are no water molecules on the right-hand side, so the coefficient of H2O is 2.

To know more about aqueous refer here

https://brainly.com/question/30215562#

#SPJ11

Other Questions
Muscle does not provide glucose for the brain during times of starvation. Why? You may choose more than one answer.A. Muscle lacks the enzymes necessary to produce free glucoseB. Muscle lacks sufficient glucose stores.C. Liver provides glucose for brainD. Muscle uses the glucose for movement to go find food.E. Glucagon prevents the secretion of glucose Revenue variances For the year, Logitom planned to sell 920,000 units at a $39 selling price. The marketing manager was asked to explain why budgeted revenue had not been achieved for that year. Investigation revealed the following information: Actual sales volume 946,000 units Actual selling price $38 per unit Calculate the sales price variance, the sale volume variance, and the total revenue variance. Note: Do not use a negative sign with your answers. Sales price variance FavorableUnfavorableNeither favorable or unfavorable Sales volume variance FavorableUnfavorableNeither favorable or unfavorable Total revenue variance FavorableUnfavorableNeither favorable or unfavorable The strategic disadvantages ofthe Persian Empire's location. What characteristics of theempire made it difficult togovern? How might thePersians address theseproblems? What is "For to everyone who has, more will be given, and he will have abundance; but from him who does not have, even what he has will be taken away. " often paraphrased as? a port serves as a channel through which several clients can exchange data with the same server or with different servers. true false which word best describes the mood of this passage? an electron has a momentum with magnitude six times the magnitude of its classical momentum. (a) find the speed of the electron. The Pierce Co. just issued a dividend of $2.35 per share on its common stock. The company is expected to maintain a constant 5 percent growth rate in its dividends indefinitely. If the stock sells for $44 a share, what is the companys cost of equity? Which statement is true about women and leadership?A. women are less effective leaders compared with menB. women are not in high level leadership positionsC. women are underrepresented in elite leadership positionsD. women all lead differently than men Your new recruiter, Todd, is giving you an update on his efforts to fill the position of sales training coordinator. Although Todd interviewed six candidates, he seems to be reporting on only one--the candidate he believes is best for the position. Throughout the discussion, Todd continues to promote the qualifications of one candidate he felt was best "from the moment he walked in the door" while ignoring the qualifications of the other five. Which of the following errors is Todd experiencing?a. Confirmation biasb. Initial meeting biasc. Personality biasd. Experience bias Water flows over two flat plates with the same laminar free stream velocity. Both plates have the same width, but Plate #2 is twice as long as Plate #1. What is the relationship between the drag force for these two plates (i.e. the ratio F_D1/F_D2). In Exercises 9-14, compute the solution of the given initial-value problem. d2 de y dr2 d2y dt2 y (0) = y(0) = 0 diy 12. +9y = sin 31 d2 14. + 4y sin 3r dr y(0) = 2, y'(0) = 0 what is the magnification needed make a bacterium (1 micrometer) appear at a size of 0.1 mm? b. create a new calculated field named travelexpense that uses the new travel function with the reside field for the countryvalue argument and the salary field for the salaryvalue argument. 11. Write the SQL code to find how many employees are in job_code 501. 12. Write the SQL code to find what is the job description of job_code 507 13. Write the SQL codes to find how many projects are available for all four of the esters you prepared, write out the balanced equation for their preparation, including drawings of the structures of the reactants and products. Please helpTo determine whether 2126.5 and 58158 are in a proportional relationship, write each ratio as a fraction in simplest form.What is 2 1/2/6.5 as a fraction in simplest form?What is 5/8/1 5/8 as a fraction in simplest form? The isoelectric point, pI, of the protein horse liver alcohol dehydrogenase is 6.8, while that of hexokinase P-II is 4.93. What is the net charge of horse liver alcohol dehydrogenase at pH5.1 ? What is the net charge of hexokinase P-II at pH5.5 ? 3. what is the coupon rate on a bond with a par value of $1,000, semi-annual coupons, 8 years until maturity, yield to maturity of 8.50 %, and price of $925.64 explain how these classes of enzymes are critical to initiating mrna decay. select the two correct statements.