Answer:
193.07 g / mol
Explanation:
Molar mass of (NH₄)₃ = 3 * (14.01 + 4 * 1.01) = 54.15
As = 74.92 and O₄ = 4 * 16 = 64
Answer is 54.15 + 74.92 + 64 = 193.07
Determine the limiting reactant (LR) and the mass (in g) of nitrogen that can be formed from 50.0 g N 2O 4 and 45.0 g N 2H 4. Some possibly useful molar masses are as follows: N 2O 4 = 92.02 g/mol, N 2H 4 = 32.05 g/mol.
N 2O 4( l) + 2 N 2H 4( l) → 3 N 2( g) + 4 H 2O( g)
a) LR = N2O4, 45.7 g N2 formed
b) LR = N2O4, 105 g N2 formed
c) LR = N2H4, 13.3 g N2 formed
d) LR = N2H4, 59.0 g N2 formed
e) No LR, 45.0 g N2 formed
Answer:
Option A. LR = N2O4, 45.7g N2 formed
Explanation:
The balanced equation for the reaction is given below:
N2O4(l) + 2N2H4(l) → 3N2(g) + 4H2O(g)
Next, we shall determine the masses of N2O4 and N2H4 that reacted and mass of N2 produced from the balanced equation. This is illustrated below:
Molar mass of N2O4 = 92.02 g/mol
Mass of N2O4 from the balanced equation = 1 x 92.02 = 92.02 g
Molar mass of N2H4 = 32.05 g/mol
Mass of N2H4 from the balanced equation = 2 x 32.05 = 64.1g
Molar mass of N2 = 2x14.01 = 28.02g/mol
Mass of N2 from the balanced equation = 3 x 28.02 = 84.06g
Summary:
From the balanced equation above,
92.02g of N2O4 reacted with 64.1g of N2H4 to produce 84.06g of N2.
Next, we shall determine the limiting reactant. This can be obtained as follow:
From the balanced equation above,
92.02g of N2O4 reacted with 64.1g of N2H4.
Therefore, 50g of N2O4 will react with = (50 x 64.1)/92.02 = 34.83g of N2H4.
From the calculations made above, we can see that only 34.83g out 45g of N2H4 is required to react completely with 50g of N2O4.
Therefore, N2O4 is the limiting reactant and N2H4 is the excess reactant.
Finally, we shall determine the mass of N2 produced from the reaction.
In this case the limiting reactant will be used as it will produce the maximum yield of N2 since all of it is used up in the reaction.
The limiting reactant is N2O4 and the mass N2 produced can be obtained as illustrated below:
From the balanced equation above,
92.02g of N2O4 reacted to produce 84.06g of N2.
Therefore 50g of N2O4 will react to produce = (50 x 84.06)/92.02 = 45.7g of N2.
Therefore, 45.7g of N2 were produced from the reaction.
At the end of the day,
The limiting reactant is N2O4 and 45.7g of N2 were produced from the reaction.
Which best describes the act of using senses or tools to gather information? creating a hypothesis making an observation summarizing the results recording the measurements
Answer:
B - Making an Observation
Explanation:
Making an observation best describes the act of using senses or tools to gather information. Therefore, option B is correct.
What are senses in the scientific method?The five senses—sight, taste, touch, hearing, and smell—gather data about our surroundings that the brain interprets. Based on prior experience (and subsequent learning), as well as by combining the data from each sensor, we make sense of this information.
Information gleaned from your five senses is referred to as an observation. These are smell, taste, touch, hearing, and sight. When you see a bird or hear it sing, you notice it.
The term observation, which is also used to sense five aspects of the world including vision, taste, touch, smell, and hearing, is used to describe utilizing the senses to examine the world, employing tools to take measurements, and looking at prior research findings.
Thus, option B is correct.
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What is the effect on the concentration of hydrofluoric acid, hydronium ion, and fluoride ion when the following are added to separate solutions of hydrofluoric acid? (a) HCl (b) KF (c) NaCl (d) KOH (e) HF
Answer:
Whenever a system in equilibrium gets disturbed, the adjustment of the system is done in such a manner that the effect of the change gets nullified, this is known as Le Chatelier's Principle. Let us consider that if a reaction present in an equilibrium gets disturbed by changing pressure, concentration, pressure, or other things, then the reaction will move in such a manner so that it can attain the equilibrium again.
Based on the given question, the equation is:
HF (aq) + H2O (l) ⇒ H3O+ (aq) + F- (aq)
a) When HCl is added, the dissociation of HCl takes place within the water to give rise to Cl- and H3O+ ions. One can witness an overall enhancement in the H3O+ ions concentration and the shifting of the equilibrium will take place in the backward direction based on the Le-Chatelier's principle. Thus, on adding HCl, the concentration of H3O+ and F- ions decreases, and the concentration of HF increases.
b) When the addition of a strong electrolyte like KF is done, the dissociation of KF is done into the F- and K+ ions. Thus, with the overall enhancement in the F- ions concentration, the shifting of equilibrium will take place in the backward direction based on the Le-Chatelier's principle. Thus, with the addition of KF, the concentration of H3O+ and F- ions decreases, and HF increases.
c) With the addition of strong electrolytes like NaCl in the solution, the dissociation of NaCl takes place into the Cl- and Na+ ions. With the addition of NaCl, the equilibrium is not disturbed as the ions exhibit no influence on the given equilibrium reaction. Thus, the concentration of H3O+, HF, and F- ions remains unmodified.
d) With the addition of KOH, the dissociation of KOH takes place into K+ and OH- ions. Based on Le-Chatelier's principle, the equilibrium will shift in the forward direction as the produced OH- ions will consume the hydronium ions. Therefore, the concentration of H3O+ and F- ions increases, while the concentration of HF decreases.
e) With the addition of HF, that is, a weak acid, the equilibrium will move in the forward direction to counter the change as the concentration of reactant increases. Therefore, the H3O+ and F- ions decreases, and the concentration of HF increases.
On adding HCl & KOH to the equilibrium concentration of hydronium ion changes, on adding KF concentration of fluoride ion changes, on adding NaCl no change occur and on adding HF concentration of both ion increases.
What is equilibrium law?According to the equilibrium law whenever any stress is applied at the equilbrium state of chemical reaction, then the equilibrium will move on that direction where the effect of the applied stress will decreases.
Given chemical reaction is:
HF (aq) + H₂O (l) ⇄ H₃O⁺ (aq) + F⁻ (aq)
If in the reaction HCl is added then it increases the concentration of H₃O⁺ as HCl will dissociate into H⁺ ion and Cl⁻ ion, so the equilibrium will shift towards the left side to maintain the concentration of H₃O⁺ ion.If KF is added in the reaction then it increases the concentration of F⁻ ion as HF will dissociates into H⁺ ion and F⁻ ion, so the equilibrium will shift towards the left side to maintain the concentration of F⁻ ion.On adding NaCl there is no change in the equilibrium as its dissociation doesn't change any concentration of the reaction.On adding KOH equilibrium will shift towards the right side, as the produced hydroxide ion will consume the hydronium ion to produce water.On adding HF reaction will move towards the right side to maintain the concentration of reactant.Hence affect on the equilibrium was discussed above.
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What is the name of Mn(CO3)2
Answer:
Mn is manganese and CO₃ is carbonate. Since the charge for CO₃ is -2 and the subscript is 2, the charge of Mn must be +4 so the answer is manganese (IV) carbonate.
Manganese (IV) carbonate is the name of Mn(CO[tex]_3[/tex])[tex]_2[/tex]. The only names used to identify salts are those of the cation or the anion.
The chemical formula of the anion (such as chloride or acetate) comes first in the name of a salt, which is followed with the identity of the cation (such as sodium or ammonium). They are created when acids and bases react, and they are always composed of either metal cations or cations made of ammonium. Manganese is Mn, and carbonate is CO[tex]_3[/tex]. The solution equals manganese (IV) carbonate since the charge for CO[tex]_3[/tex] is -2 but the subscript is 2, meaning that the charge of Mn has to be +4.
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Pb(OH)Cl, one of the lead compounds used in ancient Egyptian cosmetics, was prepared from PbO according to the following recipe: PbO(s) NaCl(aq) H2O(l) --> Pb(OH)Cl(s) NaOH(aq) How many grams of PbO and how many grams of NaCl would be required to produce 10.0 g of Pb(OH)Cl
Answer:
8.59 g
2.25 g
Explanation:
According to the given situation the calculation of grams of PbO and grams of NaCL is shown below:-
Moles of Pb(OH)CL is
[tex]= \frac{Mass}{Molar\ mass}[/tex]
[tex]= \frac{10.0 g}{259.65g / mol}[/tex]
= 0.0385 mol
Mass of PbO needed is
[tex]= 0.385mol Pb(OH) Cl\times \frac{1 mol PbO}{1molpb (OH) cl} \times \frac{223.2g PbO}{1mol PbO}[/tex]
After solving the above equation we will get
= 8.59 g
Mass of NaCL needed is
[tex]= \frac{1mol\ NaCl}{1molPb\ (OH)Cl} \times \frac{58.45NaCl}{1mol NaCl}[/tex]
After solving the above equation we will get
= 2.25 g
Therefore we have applied the above formula.
What is the specific heat of a 85.01 g piece of an unknown metal that exhibits a 45.2°C temperature change upon absorbing 1870 J of heat?
Answer:
[tex]0.48~\frac{J}{g~^{\circ}C}[/tex]
Explanation:
In this question, we have to remember the relationship between Q (heat) and the specific heat (Cp) the change in temperature (ΔT), and the mass (m).
[tex]Q=m*Cp*ΔT[/tex]
The next step is to identify what values we have:
[tex]Q~=~1870~J[/tex]
[tex]m~=~85.01~g[/tex]
[tex]ΔT~=~45.2~^{\circ}C[/tex]
[tex]Cp~=~X[/tex]
Now, we can plug the values and solve for "Cp":
[tex]1870~J=~85.01~g~*Cp*45.2~^{\circ}C[/tex]
[tex]Cp=\frac{1870~J}{85.01~g~*45.2~^{\circ}C}[/tex]
[tex]Cp=0.48~\frac{J}{g~^{\circ}C}[/tex]
The unknow metal it has a specific value of [tex]0.48~\frac{J}{g~^{\circ}C}[/tex]
I hope it helps!
When hydrocarbons are burned in a limited amount of air, both CO and CO2 form. When 0.430 g of a particular hydrocarbon was burned in air, 0.446 g of CO, 0.700 g of CO2, and 0.430 g of H2O were formed.
Required:
a. What is the empirical formula of the compound?
b. How many grams of O2 were used in the reaction?
c. How many grams would have been required for complete combustion?
Answer:
(a) The empirical formula of the compound is
m(CxHy) + m(O2) = m(CO) + m(CO2) + m(H2O).
(b) The grams of O2 that were used in the reaction is 1.146 g
(c) The amount of O2 that would have been required for complete combustion is 1.401 g.
Explanation:
a. m(CxHy) + m(O2) = m(CO) + m(CO2) + m(H2O)
(b) Using law of conservation of mass from above
m(O2) = m(CO) + m(CO2) + m(H2O) - m(CxHy)
m(O2) = 0.446 + 0.700 + 0.430 - 0.430
m(O2) = 1.146 g
The grams of O2 that were used in the reaction is 1.146 g
(c) for complete combustion, we need to oxidized CO to CO2
Then, 2CO +O2 = 2CO2
m(add)(O2) = M(O2)*¢(O2)/2 = M(O2) * {(m(CO))/(2M(CO))}
m(add)(O2) = 32 * {(0.446)/(2*28)} = 0.255 g
Note; Molar mass of O2 = 32, CO = 28
m(total)(O2) = m(O2) + m(add)(O2)
m(total)(O2) = 1.146 + 0.255 = 1.401 g
The amount of that grams would have been required for complete combustion is 1.401 g.
Note (add) and (total) were used subscript to "m"
Hypothesis 1: If you increase the
temperature of a reaction, then the reaction
rate will increase because particles experience
more collisions at higher temperatures.
To test the first hypothesis, you measured the
reaction rate for several different?
volumes.
temperatures.
densities.
particle sires.
Answer:is increase and more collisions :)
Explanation:
A student wants to prepare a salt starting with H2SO4. Select all of the compound types that can react with H2SO4 to form a salt.
1. salt
2. acid
3. acid salt
4. basic oxide
5. base
6. metal
7. acidic oxide
Answer:
4 and 6 would work for this
At what geographical location would the boiling point of water be lowest?
A. Boston, Massachusetts
B. The coast of the Atlantic Ocean
C. The Dead Sea
D. The top of Mount Everest
Answer:
I think it would be the Dead Sea
Explanation:
Because the dead sea is already usually in the warmer temperatures, the boiling point of the water would be lower than the rest.
Write the empirical formula
Answer:
[tex]1) NH_{4}IO_{3}\\2) Pb(IO_{3})_{4} \\3) NH_{4}(C_{2}H_{3}O_{2})\\4) Pb(C_{2}H_{3}O_{2})_{4}[/tex]
Explanation:
[tex]1) NH_{4}^{+}IO_{3}^{-} ---> NH_{4}IO_{3}\\2) Pb^{4+}(IO_{3}^{-})_{4} --->Pb(IO_{3})_{4} \\3) NH_{4}^{+}(C_{2}H_{3}O_{2})^{-} ---> NH_{4}(C_{2}H_{3}O_{2})\\4) Pb^{4+}(C_{2}H_{3}O_{2})^{-} _{4} --->Pb(C_{2}H_{3}O_{2})_{4}[/tex]
Description (with words) of water just above melting temperature. What intermolecular forces do you expect to find in water in liquid state
Answer:
intermolecular dipole-dipole hydrogen bonds
Explanation:
Water is a polar molecule. Recall that the central atom in water is oxygen. The molecule is bent, hence it has an overall dipole moment directed towards the oxygen atom. Since it has a permanent dipole moment, we expect that it will show dipole-dipole interactions in the liquid state.
Similarly, water contains hydrogen and oxygen. Recall that hydrogen bonds are formed when hydrogen is covalently bonded to highly electronegative elements. Hence, water in the liquid state exhibits strong hydrogen bonding. The unique type of dipole-dipole interaction in liquid water is actually hydrogen bonding, hence the answer.
Question 11: How does the energy of a photon emitted when the electron moves from the 3rd orbital to the 2nd orbital compare to the energy of a photon absorbed when the electron moves from the 2nd orbital to the 3rd orbital?
Answer:
Explanation:
The energy of a photon emitted when the electron moves from the 3rd orbital to the 2nd orbital is exactly same as the energy of a photon absorbed when the electron moves from the 2nd orbital to the 3rd orbital
What is the pressure of 5.0 Mol nitrogen (N2) gas in a 2.0 L container at 268 K?
Answer:
pressure is = 54.9802atm
Explanation:
using ideal gas equation
PV=nRT
Each unknown mixture contains 5 metal constituents. Select the 5 metal ions that you have identified as being present in your mixture. Please double check your selections before you hit the submit button. a. Ca b. Co c. Cr d. Fe e. K f. Mn g. Zn
Explanation:
A metal ion is a type of atom compound that has an electric charge.
Such atoms willingly lose electrons in order to build positive ions called cations. The selected Ions are :
[tex]1. Mn^2^+\\\ 2. Ca^2^+\\\ 3. Co^2^+\\\ 4. Fe^2^-\\\ 5. K^+[/tex]
A package contains 1.33 lb of ground round. If it contains 29% fat, how many grams of fat are in the ground round? The book is saying 91g I keep getting 175g. Can someone please explain?
Answer:
To obtain the grams of fat that the ground round has, knowing that it weighs 1.33 pounds we must pass this value to grams. Since 1 pound equals 453.59 grams, 1.33 pounds equals 603.27 (453.59 x 1.33).
Now, to obtain 29 percent of 603.27, we must make the following calculation: 603.27 / 100 x 29, which gives a total of 174.94 grams.
In this way, your reasoning is correct and it is probably a mistake in the book.
Calculate the change in entropy when 1.00 kgkg of water at 100∘C∘C is vaporized and converted to steam at 100∘C∘C. Assume that the heat of vaporization of water is 2256×103J/kg2256×103J/kg. Express your answer in joules per kelvin.
Answer:
[tex]\Delta S=6045.8\frac{J}{K}[/tex]
Explanation:
Hello,
In this case, we can compute the change in the entropy for vaporization processes in term of the enthalpy of vaporization as shown below:
[tex]\Delta S=\frac{m*\Delta H}{T}[/tex]
Whereas the temperature is in Kelvins. In such a way, the entropy results:
[tex]\Delta S=\frac{1.00kg*2256x10^3\frac{J}{kg} }{(100+273.15)K}\\\\\Delta S=6045.8\frac{J}{K}[/tex]
Best regards.
What is the half-life for the first order decay of 14C according to the reaction, 146C — 147N +e- ?
The rate constant for the decay is 1.21 x10-4 year-1
Answer:
5727 years or 5730 (rounded to match 3 sig figs) whichever one your teacher prefers
Explanation:
First Order decay has a half life formula of Half Life = Ln (2) / k = 0.693/K
Half-life = 0.693/k = 0.693/1.21 x10-4 = 5727 years or 5730 (rounded to match 3 sig figs)
This should be correct because if you google the half-life of 14 C it is ~ 5700 years
A 0.187 M weak acid solution has a pH of 3.99. Find Ka for the acid. Express your answer using two significant figures.
Answer:
5.56 × 10⁻⁸
Explanation:
Step 1: Given data
Concentration of the weak acid (Ca): 0.187 MpH of the solution: 3.99Step 2: Calculate the concentration of H⁺
We will use the following expression.
pH = -log [H⁺]
[H⁺] = antilog -pH = antilog -3.99 = 1.02 × 10⁻⁴ M
Step 3: Calculate the acid dissociation constant (Ka)
We will use the following expression.
[tex]Ka = \frac{[H^{+}]^{2} }{Ca} = \frac{(1.02 \times 10^{-4})^{2} }{0.187} = 5.56 \times 10^{-8}[/tex]
If unknown to you, your pipet was incorrectly calibrated so that it transferred less than 10.00 mL of your solution, the density you calculated for the liquid would tend to be smaller or larger than the correct value. Explain.
Answer:
The density would be larger than the correct value.
Explanation:
First off, the realtionship between denisty and volume is given in the equation below;
Density = Mass / Volume
From this equation, Density is inversely proportional to volume. This means as the volume increases, the density decreases and as the volume decreases the density increases.
Assuming all thing's being normal;
Mass = 2g
Volume = 10ml
Density = 2 / 10 = 0.2 g/ml
Second case scenario;
'your pipet was incorrectly calibrated so that it transferred less than 10.00 mL"
Lets have a value of 8ml for our volume. Mass remains constant.
Density = 2 / 8 = 0.25 g/ml
The density would be larger than the correct value.
Answer: The density would be larger than the correct value.
First off, the relationship between density and volume is given by:
Density = Mass / Volume
From this equation, Density is inversely proportional to volume. This means as the volume increases, the density decreases and as the volume decreases the density increases.
Assuming all thing's being normal;
Mass = 2g
Volume = 10ml
Density = [tex]\frac{2}{10}=0.2[/tex] g/ml
Second case scenario;
'your pipet was incorrectly calibrated so that it transferred less than 10.00 mL"
Lets have a value of 8ml for our volume. Mass remains constant.
Density = [tex]\frac{2}{8}= 0.25[/tex] g/ml
The density would be larger than the correct value.
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The acid dissociation constant Ka equals 1.26 × 10–2 for HSO4– (acid 1) and is 5.6 × 10–10for NH4+(acid 2). Predict the net direction of the following reaction: HSO4–(aq) + NH3(aq) SO42–(aq) + NH4+(aq)
Answer:
As K >>> 1, the reaction will shift to the products
Explanation:
To know the direction of any reaction you must calculate the equilibrium constant, K. If K is < 1, the reaction will shift to the reactants and if k > 1 the reaction will shift to the products.
With the reactions:
HSO₄⁻ ⇄ SO₄²⁻ + H⁺ Ka = 1.26x10⁻²
And:
NH₄⁺ ⇄ NH₃⁺ + H⁺ Ka = 5.6x10⁻¹⁰
The inverse reaction:
NH₃⁺ + H⁺ ⇄ NH₄⁺ 1/Ka = 1.8x10⁹
The sum of the reactions:
HSO₄⁻ + NH₃⁺ + H⁺ ⇄ NH₄⁺ + SO₄²⁻ + H⁺ K = 1.26x10⁻² ₓ 1.8x10⁹ = 2.3x10⁷
As K >>> 1, the reaction will shift to the productsChoose the situation below that would result in an endothermic ΔHsolution.
a) When |ΔHsolute| > |ΔHhydration|
b) When |ΔHsolute| is close to |ΔHhydration|
c) When |ΔHsolute| < |ΔHhydration|
d) When |ΔHsolvent| >> |ΔHsolute|
e) There isn't enough information to determine.
Answer:
Option A - When |ΔHsolute| > |ΔHhydration|
Explanation:
A solution is defined as a homogeneous mixture of 2 or more substances that can either be in the gas phase, liquid phase, solid phase.
The enthalpy of solution can either be positive (endothermic) or negative (exothermic).
Now, we know that enthalpy is amount of heat released or absorbed during the dissolving process at constant pressure.
Now, the first step in thus process involves breaking up of the solute. This involves breaking up all the intermolecular forces holding the solute together. This means that the solute molecules are separate from each other and the process is always endothermic because it requires energy to break interaction. Thus;
The enthalpy ΔH1 > 0.
Thus, the enthalpy of the solute has to be greater than the enthalpy of hydration.
An endothermic ΔHsolution occurs when |ΔH solute| < |ΔH hydration|.
A substance dissolves in water when the solute - solvent interaction exceeds the solute - solute solute interaction. The energy required to break the bonds between solutes is the ΔHsolute and the energy released when solute - solvent interaction take place is called the ΔHhydration.
We know that when |ΔH solute| < |ΔH hydration|, energy is required to break up the solute - solute interaction and ΔHsolution is endothermic.
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"Calculate the pH during the titration of 20.00 mL of 0.1000 M HF(aq) with 0.2000 M NaOH(aq) after 9.4 mL of the base have been added. Ka of hydrofluoric acid
Answer:
The answer is " 10.39"
Explanation:
Calculating acid moles:
[tex]= 0.02000 \ L \times 0.1000 \ M \\\\= 0.002000[/tex]
Calculating NaOH moles:
[tex]= 0.02012 \ L \times 0.1000 \ M \\\\= 0.002012[/tex]
calculating excess in OH- Moles:
[tex]= 0.002012 - 0.002000\\\\=0.000012[/tex]
calculating total volume:
[tex]= 20.00 + 20.12\\\\ = 40.12 mL \\\\= 0.04012 L[/tex]
[tex][OH-]= \frac{0.000012} { 0.0472}[/tex]
[tex]=0.00025 M[/tex]
[tex]pOH = - \log 0.00025[/tex]
= 3.6
[tex]pH = 14 - pOH[/tex]
= 10.39
Turn on Write equation. What you see is an equation that shows the original uranium atom on the left. The boxes on the right represent the daughter product—the atom produced by radioactive decay—and the emitted alpha particle.
Answer:
Uranium-238 undergoes alpha decay to form Thorium-234 as daughter product.
Explanation:
Alpha decay is indicative of loss of the equivalents of a helium particle emission. The reaction equation for this reaction is shown below:
[tex]_{92} ^{238} U_{}[/tex]→ [tex]_{90} ^{234} Th_{} + _{2} ^{4} He_{}[/tex]
I hope this explanation is clear and explanatory.
Can a catalyst change an exothermic reaction into an endothermic reaction or vice versa? Please explain your answer.
Answer:
A catalyst cannot change an exothermic reaction into an endothermic reaction or vice versa.
Explanation:
Catalyst is basically a substance that enables a chemical reaction to occur at a faster rate as compared to the reaction without catalysis. It lowers the activation energy and temperature for a chemical reaction and a catalyst itself does not goes through any permanent chemical change. This means it does not get used in the process.
Exothermic and endothermic are the chemical reaction. Exothermic reactions absorb energy. This energy is absorbed in the form of heat. When the energy is released in the form of heat then this reaction is called endothermic. So one absorbs the heat and the other releases it.
As we know that the catalyst does not undergo change at the end of the reaction so the energy or heat whether is absorbed or emitted or you can say whether the reaction is exothermic or endothermic, the total energy stays unchanged during the reaction. So with and without a catalyst, if both have same reactants and products and the difference in enthalpy between products and reactants will be the same.
A pentavalent cation atom has 20 and 15 neutrons as protons. Find the electron quantity and mass number respectively. (40 pts.) a) 20 and 15 b) 15 and 20 c) 15 and 35 d) 35 and 15 e) 10 and 20
Answer:
C.
Explanation:
Since the mass number is the number of protons and neutrons added together, the answer is 35. Since the questions are respectively electron quantity and mass number, the only answer choice with 35 as the second choice is C, so that is the correct answer.
how do you fight off ADHD medication
Answer:A medication break can ease side effects. A lack of appetite, weight loss, sleep troubles, headaches, and stomach pain are common side effects of ADHD medication.
Explanation: It may boost your child’s growth. Some ADHD medications can slow a child’s growth in height, especially during the first 2 years of taking it. While height delays are temporary and kids typically catch up later, going off medication may lead to fewer growth delays.
It won’t hurt your child. Taking a child off ADHD medication may cause their ADHD symptoms to reappear. But it won’t make them sick or cause other side effects.
What volume of 6.00 M hydrochloric acid is needed to prepare 500 mL of 0.100 M solution?
Answer:
8.33mL or .0083L
Explanation:
Use m1 * V1 = m2 * V2
6.00M(x) = 0.100M(500mL)
solve for x
x= (.1 * 500) / 6
x=8.333 mL
Based on the type or types of intermolecular forces, predict the substance in each pair that has the higher boiling point Given the molecules propane (C3H8) and n-butane (C4H10)_________ has the higher boiling point mainly due to_______ Given the molecules diethyl ether (CH3 CH2OCH2 CH3) and 1-butanol (CH3 CH2CH2 CH2OH) higher boiling point mainly due to______________ .
Answer:
See explanation
Explanation:
-) Given the molecules propane (C3H8) and n-butane (C4H10) n-butane has the higher boiling point mainly due to a larger chain of carbons.
In this question, in propane, we have a chain of three carbons. In butane, we have fourth carbons. If we have more carbons we will have more interactions. If we have more interactions we have to give more energy to go from liquid to gas, therefore we will have a higher boiling point.
-) Given the molecules diethyl ether (CH3 CH2OCH2 CH3) and 1-butanol (CH3 CH2CH2 CH2OH) 1-butanol has a higher boiling point mainly due to hydrogen bonding.
In the case of butanol, we have the "OH" group. If we have a hydrogen bond to a heteroatom (O, S, P, or N) we will have the presence of this type of interaction between molecules. If we have more interactions we have to give more energy to go from liquid to gas, therefore we will have a higher boiling point.
I hope it helps!
A chemist measures the energy change Delta H during the following
2Fe2O3(s)->4FeO(s)+O2(g).
1) this reactions is: Endothermic or exothermic.
2) suppose 94.2g of Fe2O3 react. will any heat be relased or absorbed. yes absorbed. yes releases. no.
3) If you said heat will be released or absorbed in the second part of the question. calculate how much heat will be absored or released. be sure your answer has correct number of significant digits.
Answer: 1) Endothermic
2) Yes, absorbed.
3) 166.86 kJ will be absorbed.
Explanation:
1) To determine if a reaction is endothermic (heat is absorbed by the system) or exothermic (heat is released by the system), first calculate its change in Enthalpy, which is given by:
ΔH = [tex]H_{products} - H_{reagents}[/tex]
For the reaction 2Fe₂O₃(s) ⇒ 4FeO(s) + O₂(g):
Enthalpy of Reagent (Fe₂O₃(s))
Enthalpy of formation for Fe₂O₃(s) is - 822.2 kJ/mol
The reaction needs 2 mols of the molecule, so:
H = 2(-822.2)
H = - 1644.4
Enthalpy of Products (4FeO(s) + O₂(g))
Enthalpy of formation of O₂ is 0, because it is in its standard state.
Enthalpy of formation of FeO is - 272.04 kJ/mol
The reaction produces 4 mols of iron oxide, so:
H = 4(-272.04)
H = -1088.16
Change in Enthalpy:
ΔH = [tex]H_{products} - H_{reagents}[/tex]
ΔH = - 1088.16 - (-1644.4)
ΔH = + 556.2 kJ/mol
The change in enthalpy is positive, which means that the reaction is absorving heat. Then, the chemical reaction is Endothermic.
2) When Fe₂O₃(s) reacts, heat is absorbed because it is an endothermic reaction.
3) Calculate how many mols there is in 94.2 g of Fe₂O₃(s):
n = [tex]\frac{mass}{molar mass}[/tex]
n = [tex]\frac{94.2}{160}[/tex]
n = 0.6 mols
In the reaction, for 2 mols of Fe₂O₃(s), 556.2 kJ are absorbed. Then:
2 mols --------------- 556.2 kJ
0.6 mols ------------- x
x = [tex]\frac{0.6*556.2}{2}[/tex]
x = 167 kJ
It will be absorbed 167 kJ of energy, when 94.2 g of Fe₂O₃(s) reacts.