the equilibrium constant at 250C for the equation PCl5 PCl3 is kp 4.5 x 10^3 bar calculate value of grxn at 250C in which direction is reaction spontaneous when pcl3 cl2 standard conditions

Answers

Answer 1

Answer:

-36.6 kJ·mol⁻¹  

Explanation:

1. Calculate ΔG

[tex]\text{The relationship between $\Delta G^{\circ}$ and K is}\\\Delta G^{\circ} = -RT \ln K[/tex]

T = (250 + 273.15) K = 523.15 K

[tex]\begin{array}{rcl}\Delta G & = & -8.314 \text{ J}\cdot\text{K}^{-1} \text{mol}^{-1} \times \text{523.15 K} \ln (4.5 \times 10^{3}) \\& = & -4349\text{ J}\cdot \text{mol}^{-1} \times 8.412\\& = & \text{-36 590 J}\cdot \text{mol}^{-1}\\& = & \textbf{-36.6 kJ}\cdot \text{mol}^{-1}\\\end{array}[/tex]

2. Direction of spontaneity

ΔG is negative, so the reaction is spontaneous in the forward direction.


Related Questions

Why do you think sodium bicarbonate is included to neutralize an acidic spill rather than sodium hydroxide?
Imagine a hypothetical situation in which 250 mL of diethyl ether (SDS) has spilled inside of a chemical fume hood onto a stir plate that is plugged in and stirring. Discuss the risks associated with this situation (location, size, compound spilled, and external hazards), and then explain how this spill should be managed.

Answers

Answer:

Acid spills should be neutralized with sodium bicarbonate and then cleaned up with a paper towel or sponge.

Explanation:

Which resulted from the study of chemistry?

A) Alchemy to turn base metals into noble metals

B) The understanding of earth, air, fire, and water as the basic components of matter.

C) A supernatural, mystical view of the world.

D) Discovering the role of oxygen in combustion

Answers

the answer is C
A supernatural, mystical view of the world

Help please.☺️☺️☺️☺️☺️

Answers

Answer:

A.∆s>0contribute to spontaneity.

How many grams of sodium phosphate are needed to have 1.67 moles of sodium ion?

Answers

Answer:

91.29 g of Na₃PO₄ are needed to produce 1.67 moles of sodium ions.

Explanation:

The formula for sodium phosphate is Na₃PO₄

Molar mass of sodium phosphate = 164 g/mol

The dissociation of one mole of sodium phosphate produces 3 moles of sodium ions;

Na₃PO₄ ------> 3Na⁺ + PO₄³

Number of moles of Na₃PO₄ that will produce 1.67 moles of Na⁺ = 1/3 * 1.67 = 0.556 moles  of Na₃PO₄

Mass of 0.556 moles of Na₃PO₄ = 0.556 moles * 164 g/mol = 91.29 g

Therefore, 91.29 g of Na₃PO₄ are needed to produce 1.67 moles of sodium ions.

What is the pH of a 0.02M solution of sodium acetate (pka=4.74) to which you add HCl to a final concentration of 0.015M?

Answers

Answer:

pH = 5.22

Explanation:

As you can see, your initial concentration of sodium acetate (NaCH₃COO) is 0.02M (0.02mol /L). When you add HCl, the reaction is:

NaCH₃COO + HCl → CH₃COOH + NaCl.

If you add HCl, and final concentration of NaCH₃COO is 0.015M, the concentration of CH₃COOH is 0.005M.

You can know the pH of this solution using H-H equation:

pH = pKa + log {NaCH₃COO} / {CH₃COOH}

pH = 4.74 +  log {0.015M} / {0.005M}

pH = 5.22

some students believe that teachers are full of hot air. If I inhale 3.5 liters of gas at a temperature of 19 degrees Celsius and it heats to a temperature of 58 degrees celsius in my lungs. what is the new volume of the gas?

Answers

Answer:

3.97 L

Explanation:

Data obtained from the question include the following:

Initial volume (V1) = 3.5 L

Initial temperature (T1) = 19 °C

Final temperature (T2) = 58 °C

Final volume (V2) =..?

Next, we shall convert celsius temperature to Kelvin temperature. This can be done as shown below:

Temperature (K) = temperature (°C) + 273

T (K) = T (°C) + 273

Initial temperature (T1) = 19 °C

Initial temperature (T1) = 19 °C + 273 = 292 K

Final temperature (T2) = 58 °C

Final temperature (T2) = 58 °C + 273 = 331 K

Finally, we shall determine the new volume of the gas by using Charles' law equation as shown below:

Initial volume (V1) = 3.5 L

Initial temperature (T1) = 292 K

Final temperature (T2) = 331 K

Final volume (V2) =..?

V1 /T1 = V2 /T2

3.5 /292 = V2 /331

Cross multiply

292 x V2 = 3.5 x 331

Divide both side by 292

V2 = (3.5 x 331) / 292

V2 = 3.97 L

Therefore, the new volume of the gas is 3.97 L.

Carbon-14 has a half-life of 5720 years and this is a fast-order reaction. If a piece of wood has converted 75 % of the carbon-14, then how old is it?

Answers

Answer:

11445.8years

Explanation:

Half-life of carbon-14 = 5720 years

First we have to calculate the rate constant, we use the formula :

What is the name of the molecule below?
A) 2-pentene
B) pentane
C) 2-pentyne
D) 2-pentane​

Answers

The name of the molecule which is given below is 2-pentene.

What are alkene?

Alkenes are the organic compounds which are composed of carbon and hydrogen atoms, in which double bond is present.

In the given diagram:

Each corner and joints shows the carbon atoms and number of carbon atoms in it is 5.One double bond is present in the 2nd position.

So the compound is 2 pentene.

Hence, 2 pentene is the name of the compound.

To know more about alkene, visit the below link:
https://brainly.com/question/6041165

#SPJ2

Arrange the following kinds of electromagnetic radiation in order of increasing wavelength: infrared, green light, red light, radio waves, X rays, ultraviolet light.
Rank from shortest to longest. To rank items as equivalent, overlap them.
infrared
green light
red light
radio waves
X rays
ultraviolet

Answers

Answer:

In the other of increasing wavelength we arrange as

X-rays

ultraviolet

green light

red light

infrared

radio waves

Explanation:

In the electromagnetic spectrum, wavelength decreases with increase in the energy of the electromagnetic wave. Since the e-m wave spectrum is arranged in the order of increasing energy (decreasing wavelength) as: Radio wave; infrared; visible light; ultraviolet; x-rays; gamma rays. Within the visible light, the green light has more energy than the red light. Therefore, the arrangement should be in the reverse direction of their increasing energy.

The decomposition of hydrogen peroxide to form water and oxygen gas releases 196.6 kJ per mole of hydrogen peroxide. This reaction occurs when hydrogen peroxide is placed on a cut to sterilize it. How much heat is released when 5.70 mol H2O2 decompose

Answers

Answer:

1120.62 kJ

Explanation:

In order to find how much heat is released for 7.70 mol, we have to compare it with the heat released from one mole.

So from the question, we have;

196.6 kJ = 1 mol

x = 5.70

x = 5.70 * 196.6 / 1

x = 1120.62 kJ

How many grams are in 5.87 x 10^21 molecules of sulfur?

Answers

Answer:

0.312g

Explanation:

From Avogadro's hypothesis, 1mole of any substance contains 6.02x10^23 molecules. This means that 1mole of sulphur also contains 6.02x10^23 molecules

1mole of sulphur = 32g

If 1 mole(i.e 32g) of sulphur contains 6.02x10^23 molecules

Then, Xg of sulphur will contain 5.87x10^21 molecules i.e

Xg of sulphur = (32x5.87x10^21)/6.02x10^23 = 0.312g

just saying this is not my work, thank Eduard22sly

he answered it on a different page

so give him credit

here is the link

https://brainly.com/question/14966520

The final overall chemical equation is Upper Ca upper O (s) plus upper C upper O subscript 2 (g) right arrow upper C a upper C upper O subscript 3 (s).. When the enthalpy of this overall chemical equation is calculated, the enthalpy of the second intermediate equation is halved and has its sign changed. is halved. has its sign changed. is unchanged.

Answers

Answer:

the enthalpy of the second intermediate equation is halved and has its sign changed.

Explanation:

Let us take a look at the first and second intermediate reactions as well as the overall reaction equation for the process under review;

First reaction;

Ca (s) + CO₂ (g) + ½O₂ (g) → CaCO₃ (s) ΔH₁ = -812.8 kJ

Second reaction;

2Ca (s) + O₂ (g) → 2CaO (s) ΔH₂ = -1269 kJ

Hence the overall equation is now;

CaO (s) + CO₂ (g) → CaCO₃ (s) ΔH = ?

According to the Hess law of constant heat summation, the enthalpy of the overall reaction is supposed to be obtained as a sum of the enthalpy of both reactions but this will not give the enthalpy of the overall reaction in this case. The enthalpy of the overall reaction is rather obtained by halving the enthalpy of the second intermediate reaction and reversing its sign before taking the sum as shown below;

Enthalpy of Intermediate reaction 1 + ½(- Enthalpy of Intermediate reaction 2) = Enthalpy of Overall reaction

Answer:

A.

Explanation:

Did it on Edge.

Determine the cell notation for the redox reaction given below.

Sn(s) + 2H+(aq) ⟶ Sn2+(aq) + H2(g)

a. H+(aq) | H2(g) | Pt ∥ Sn(s) | Sn2+(aq)
b. H2(g) | H+(aq) | Pt ∥ Sn2+(aq) | Sn(s)
c. Sn2+(aq) | Sn(s) ∥ H2(g) | H+(aq) | Pt
d. Sn(s) | Sn2+(aq) ∥ H+(aq) | H2(g) | Pt
e. Sn(s) | H2(g) ∥ Sn2+(aq) | H+(aq) | Pt

Answers

Answer:

The correct answer is d. Sn(s) | Sn²⁺(aq) ∥ H⁺(aq) | H₂(g) | Pt

Explanation:

The half reactions are:

2H⁺(aq) + 2 e- ⟶ H₂(g) (reduction)

Sn(s) ⟶ Sn²⁺(aq) + 2 e-  (oxidation)

In the cell notation, there are two electrodes in which are separated the reduction reaction from the oxidation reaction. In the left electrode occurs the oxidation reaction (anode) while in the right electrode occurs the reduction reaction (cathode). The general form of the cell notation is the following:

anode reaction∥ cathode reaction

where the two bars ( ∥ ) represent the physical barrier between the electrodes. A single bar ( | ) is used to represent a phase separation.  

In this redox reaction, the half reaction of the anode is Sn(s) ⟶ Sn²⁺(aq) + 2 e-; whereas the half reaction of the cathode is 2H⁺(aq) + 2 e- ⟶ H₂(g).

The componens are written in order according to the half reaction. Since Sn²⁺ and H⁺ ions are in solution, a platinum electrode is used and represented as Pt. Thus, the cell notation is:

Sn(s) | Sn²⁺(aq) ∥ H⁺(aq) | H₂(g) | Pt

A chemistry student weighs out of formic acid into a volumetric flask and dilutes to the mark with distilled water. He plans to titrate the acid with solution. Calculate the volume of solution the student will need to add to reach the equivalence point. Round your answer to significant digits.

Answers

The given question is incomplete, the complete question is:

A chemistry student weighs out 0.0349g of formic acid HCHO2 into a 250.mL volumetric flask and dilutes to the mark with distilled water. He plans to titrate the acid with 0.1500M NaOH solution. Calculate the volume of NaOH solution the student will need to add to reach the equivalence point. Round your answer to 3 significant digits.

Answer:

The correct answer is 5.06 ml.

Explanation:

Based on the given information, the weight of formic acid given is 0.0349 grams. The volume of formic acid of V1 given is 250 ml. The molecular mass of formic acid is 46 grams per mole. Now the molarity of formic acid will be,  

[HCOOH] = weight * 1000 / molecular mass * volume (ml)

= 0.0349 * 1000 / 46 * 250

= 0.003035 M or M1

The molarity of NaOH given is 0.1500 M or M2

Let us assume that the volume needed to attain equivalence point is V2 ml.  The volume V2 can be determined by using the dilution equation,  

M1V1 = M2V2

V2 = M1V1/M2  

V2 = 0.003035 * 250 / 0.1500

V2 = 5.06 ml.  

Hence, the volume of NaOH needed is 5.06 ml.  

Drag each image to the correct location on the model. Each image can be used more than once. Apply the rules and principles of electron configuration to draw the orbital diagram of aluminum. Use the periodic table to help you.

Answers

Answer:

The answer to your question is given below.

Explanation:

Aluminium has atomic number of 13. Thus, the electronic configuration of aluminium can be written as:

Al (13) —› 1s² 2s²2p⁶ 3s²3p¹

The orbital diagram is shown on the attached photo.

Answer: screen shot

Explanation:

1. The following thermochemical equation is for the reaction of water(l) to form hydrogen(g) and oxygen(g). 2H2O(l)2H2(g) + O2(g) H = 572 kJ How many grams of H2O(l) would be made to react if 110 kJ of energy were provided? _____ grams
2. The following thermochemical equation is for the reaction of carbon monoxide(g) with hydrogen(g) to form methane(g) and water(g). CO(g) + 3H2(g) CH4(g) + H2O(g) H = -206 kJ When 6.27 grams of carbon monoxide(g) react with excess hydrogen(g),_____ kJ of energy are ____ a.evolved b.absorbed

Answers

Answer:

1. 6.92 g of H2O

2i. - 46 KJ of energy.

ii. Option A. Evolved.

Explanation:

1. Determination of the mass of H2O that would be made to react if 110 kJ of energy were provided.

This can be obtained as follow:

The equation for the reaction is given below

2H2O(l) —> 2H2(g) + O2(g) H = 572 kJ

Next, we shall determine the mass of H2O required to produce 572 kJ from the balanced equation.

Molar mass of H2O = (2x1) + 16 = 18 g/mol

Mass of H2O from the balanced equation = 2 x 18 = 36 g

From the balanced equation above, 36 g of H2O reacted to produce 572 kJ of energy.

Finally, we shall determine the mass of water (H2O) needed to produce 110 kJ of energy.

This is illustrated below:

From the balanced equation above, 36 g of H2O reacted to produce 572 kJ of energy.

Therefore, Xg of H2O will react to 110 kJ of energy i.e

Xg of H2O = (36 x 110)/572

Xg of H2O = 6.92 g

Therefore, 6.92 g of H2O is needed to react in order to produce 110 KJ of energy.

2i. Determination of the energy.

The balanced equation for the reaction is given below:

CO(g) + 3H2(g) —> CH4(g) + H2O(g) H = -206 kJ

Next, we shall determine the mass of CO that reacted to produce -206 kJ of energy from the balanced equation.

This is illustrated below:

Molar mass of CO = 12 + 16 = 28 g/mol

Mass of CO from the balanced equation = 1 x 28 = 28 g

From the balanced equation above,

28 g of CO reacted to produce -206 kJ of energy.

Finally, we shall determine the amount of energy produced by reacting 6.27 g of CO. This is illustrated below:

From the balanced equation above,

28 g of CO reacted to produce -206 kJ of energy.

Therefore, 6.27 g of CO will react to produce = (6.27 x -206)/28 = - 46 KJ of energy.

Therefore, - 46 KJ of energy were produced from the reaction.

2ii. Since the energy obtained is negative, it means heat has been given off to the surroundings.

Therefore, the heat is evolved.

Find the molecular formula of each compound CCl , 189.83 g/mol C3H2N , 156.23 g/mol

Answers

Answer:

Explanation:

The given formula is empirical formula

Let the molecular formula of first be

[tex]( CCl )_n[/tex]

molecular weight = n x ( 12 + 35.5 )

= 47.5 n

Given molecular weight = 189.83 so

47.5 n = 189.83

n = 3.99 or 4 approx

Molecular formula =

[tex]( CCl )_4[/tex]

= C₄ Cl₄

Let the molecular formula of second compound  be

[tex]( C_3H_2N)_n[/tex]

molecular weight = n x ( 3 x 12 +2+14 )

= 52 n

Given molecular weight = 156.23  so

52 n = 156.23

n = 3.0044 or 3 approx

Molecular formula =

[tex]( C_3H_2N )_3[/tex]

= C₉H₆ N₃

Predict the order of acid strengths in the following series of cationic
species: CH3CH2NH3
+, CH3CH=NH2

Answers

Answer:

CH3CH=NH2+>CH3CH2NH3+

Explanation:

If we look at the both species under review, we will realize that they are both amines hence they possess the polar N-H bond.

Electrons are ordinarily attracted towards the nitrogen atom hence making both compounds acidic. It is worthy of note that certain features of a compound may make it more acidic than another of close structural proximity. 'More acidic' simply means that the proton is more easily lost.

CH3CH=NH2+ contains an sp2 hybridized carbon atom which is highly electronegative and further withdraws electron density from the N-H bond thereby leading to a greater acidity of CH3CH=NH2+ compared to CH3CH2NH3+

If the heat of combustion for a specific compound is −1380.0 kJ/mol and its molar mass is 44.53 g/mol, how many grams of this compound must you burn to release 822.00 kJ of heat?mass:g

Answers

Answer:

Mass = 26.53 g

Explanation:

Heat of combustion = −1380.0 kJ/mol

This means 1 mol of the compound releases 1380 kJ

Molar mass = 44.53 g/mol

This means 1 mol of the compound has a mass of 44.53 g

How many grams would release 822kJ..?

First, we have to obtain the number of moles

1 mol = 1380

x = 822

x = 0.5957 moles

Moles = Mass / Molar mass

Mass = Molar mass * moles

Mass = 44.53 * 0.5957

Mass = 26.53 g

how salt solution can be determined by using hydrometer​

Answers

Answer:

Salt solution may be calculated by measuring the specific gravity of a sample of water using a hydrometer.

Hope this answer correct (^^)....

Cyclohexane (C6H12) undergoes a molecular rearrangement in the presence of AlCl3 to form methylcyclopentane (CH3C5H9) according to the equation: C6H12 ⇌ CH3C5H9 If Kc = 0.143 at 25°C for this reaction predict the direction in which the system

Answers

Answer:

The reaction will shift leftwards, towards the formation of more cyclohexane at 25 °C

Explanation:

Hello,

In this case, for the given chemical reaction, we can write the law of mass action (equilibrium expression) as shown below:

[tex]Kc=\frac{[CH_3C_5H_9]}{[C_6H_{12} ]}[/tex]

Thus, since Kc < 1, we can conclude there are more moles of cyclohexane at equilibrium (denominator is greater than numerator), therefore, the reaction will shift leftwards, towards the formation of more cyclohexane at 25 °C.

Best regards.

Which of the following involves a decrease in entropy? Group of answer choices the dissolution of NaCl in water the evaporation of ethanol the sublimation of carbon dioxide the decomposition of N2O4(g) to NO2(g) the freezing of liquid water into ice

Answers

Answer:

the freezing of liquid water into ice

Explanation:

Entropy is the degree of disorderliness of a system, entropy is an extensive property of a thermodynamic system. An extensive property of a system is one whose value changes with the number of particles or the amount of matter present in the system.

Gases possess the greatest entropy among the States of matter followed by liquids and lastly solids. Solid particles do not translate because they are held by strong intermolecular forces.

Hence, a change from liquid to solid implies a decrease in entropy since the solid state possesses less entropy in comparison to the liquid state, hence the answer.

Calculate how much acetylene (C2H2) will be produced from 358 g of H2O and an excess of CaC2 if the percent yield for this reaction is 94.5%. CaC2 2 H2O --> C2H2 Ca(OH)2

Answers

Answer:

244.7 g of acetylene

Explanation:

The balanced reaction equation is shown below;

2H20 (l) + CaC2 (s) → Ca(OH)2 (s) + C2H2 (g)

Number of moles of were reacted = reacting mass/molar mass = 358g/18gmol-1 = 19.89 moles of water

From the balanced reaction equation;

2 moles water yields 1 mole of acetylene

19.89 moles of water will yield 19.89 × 1/2 = 9.945 moles of acetylene

Theoretical yield of acetylene = 9.945 moles of acetylene × molar mass of acetylene

Molar mass of acetylene = 26.04 g/mol

Theoretical yield of acetylene = 9.945 moles of acetylene × 26.04 g/mol

Theoretical yield of acetylene = 258.9678 g of acetylene

% yield = actual yield/ theoretical yield × 100

94.5 = actual yield/258.9678 g × 100

Actual yield= 94.5 × 258.9678 g/100

Actual yield = 244.7 g of acetylene

Air contains nitrogen, oxygen, argon, and trace gases. Ifthe partial pressure of nitrogen is 592 mm Hg, oxygen is160 mm Hg, argon is 7 mm Hg, and trace gas is 1 mm Hg,what is the atmospheric pressure

Answers

Answer:

760 mmHg

Explanation:

Step 1: Given data

Partial pressure of nitrogen (pN₂): 592 mmHgPartial pressure of oxygen (pO₂): 160 mmHgPartial pressure of argon (pAr): 7 mmHgPartial pressure of the trace gas (pt): 1 mmHg

Step 2: Calculate the atmospheric pressure

Since air is a gaseous mixture, the atmospheric pressure is equal to the sum of the gases that compose it.

P = pN₂ + pO₂ + pAr + pt = 592 mmHg + 160 mmHg + 7 mmHg + 1 mmHg = 760 mmHg

consider the following reaction
N2 + 3H2=2NH3
if 30 dm3 of each reactant react together then the volume of mixture at the end is
a 10 dm3
b 20 dm3
c 30 dm3
d 40 dm3

Answers

Answer:

d, 40 dm3.

Explanation:

According to Avogadro's law, the mole ratio of chemicals in a reaction is equal to the ratio of volumes of chemicals reacted (for gas).

From the equation, the mole ratio of N2 : H2 : NH3 = 1 : 3 : 2, meaning 1 mole of N2 reacts completely with 3 moles of H2 to give 2 moles of NH3, the ratio of volume required is also equal to 1 : 3 : 2.

Considering both N2 and H2 have 30dm3 of volume, but 1 mole of N2 reacts completely with 3 moles of H2, so we can see H2 is limiting while N2 is in excess. Using the ratio, we can deduce that 10dm3 equals to 1 in ratio (because 3 moles ratio = 30dm3).

With that being said, all H2 has reacted, meaning there's no volume of H2 left.  2 moles of NH3 is produced, meaning the volume of NH3 produced = 10 x 2 = 20 dm3. (using the ratio again)

1 mole of N2 has reacted, meaning from the  30dm3, only 10 dm3 has reacted. This also indicate that 20 dm3 of N2 has not been reacted.

So at the end, the mixture contains 20dm3 of NH3, and 20 dm3 of unreacted N2. Hence, the answer is d, 40 dm3.

Suppose you titrate 25.00 mL of 0.200 M KOBr with 0.200M H2SO4. The pH at half-equivalence point is 7.75 a). What is the initial pH of the 25.00mL of 0.200M KOBr mentioned above

Answers

Answer:

Approximately [tex]10.88[/tex].

Explanation:

Equilibrium constant

[tex]\rm OBr^{-}[/tex] can act as a weak Bronsted-Lowry base:

[tex]\rm OBr^{-}\; (aq) + H_2O\; (l) \rightleftharpoons HOBr\; (l) + OH^{-}\; (aq)[/tex].

(Side note: the state symbol of [tex]\rm HOBr[/tex] in this equation is [tex]\rm (l)[/tex] (meaning liquid) because [tex]\rm HOBr[/tex] is a weak acid.)

However, the equilibrium constant of this reaction, [tex]K_\text{eq}[/tex], isn't directly given. The idea is to find [tex]K_\text{eq}[/tex] using the [tex]\rm pH[/tex] value at the half-equivalence point. Keep in mind that this system is at equilibrium all the time during the titration. If temperature stays the same, then the same [tex]K_\text{eq}[/tex] value could also be used to find the [tex]\rm pH[/tex] of the solution before the acid was added.

At equilibrium:

[tex]\displaystyle K_\text{eq} = \frac{[\rm HOBr\; (l)]\cdot [\rm OH^{-}\; (aq)]}{[\rm OBr^{-}\; (aq)]}[/tex].

At the half-equivalence point of this titration, exactly half of the base, [tex]\rm OBr^{-}[/tex], has been converted to its conjugate acid, [tex]\rm HOBr[/tex]. Therefore, the half-equivalence concentration of [tex]\rm OBr^{-}[/tex] and [tex]\rm HOBr[/tex] should both be equal to one-half the initial concentration of [tex]\rm OBr^{-}[/tex].

As a result, the half-equivalence concentration of [tex]\rm OBr^{-}[/tex] and [tex]\rm HOBr[/tex] should be the same. The expression for [tex]K_\text{eq}[/tex] can thus be simplified:

[tex]\begin{aligned}& K_\text{eq} \\&= \frac{\left(\text{half-equivalence $[\rm HOBr\; (l)]$}\right)\cdot \left(\text{half-equivalence $[\rm OH^{-}\; (aq)]$}\right)}{\text{half-equivalence $[\rm OBr^{-}\; (l)]$}}\\ &=\text{half-equivalence $[\rm OH^{-}\; (aq)]$}\end{aligned}[/tex].

In other words, the [tex]K_\text{eq}[/tex] of this system is equal to the [tex]\rm OH^{-}[/tex] concentration at the half-equivalence point. Assume that [tex]\rm p\mathnormal{K}_\text{w}[/tex] the self-ionization constant of water, is [tex]14[/tex]. The concentration of [tex]\rm OH^{-}[/tex] can be found from the [tex]\rm pH[/tex] value:

[tex]\begin{aligned}& \text{half-equivalence $[\rm OH^{-}\; (aq)]$} \\ &= 10^{\rm pH - p\mathnormal{K}_\text{w}}\;\rm mol \cdot L^{-1} \\ &= 10^{7.75 - 14}\; \rm mol \cdot L^{-1}\\ &= 10^{-6.25}\; \rm mol \cdot L^{-1}\end{aligned}[/tex].

Therefore, [tex]\begin{aligned} K_\text{eq} &= 10^{-6.25}\end{aligned}[/tex].

Initial pH of the solution

Again, since [tex]\rm KOBr[/tex] is a soluble salt, all that [tex]0.200\; \rm M[/tex] of [tex]\rm KOBr[/tex] in this solution will be in the form of [tex]\rm K^{+}[/tex] and [tex]\rm OBr^{-}[/tex] ions. Before any hydrolysis takes place, the concentration of [tex]\rm OBr^{-}[/tex] should be equal to that of [tex]\rm KOBr[/tex]. Therefore:

[tex]\text{$[\rm OBr^{-}\; (aq)]$ before hydrolysis} = 0.200\; \rm M[/tex].

Let the equilibrium concentration of [tex][\rm OH^{-}\; (aq)][/tex] be [tex]x\; \rm M[/tex]. Create a RICE table for this reversible reaction:

[tex]\begin{array}{c|ccccccc} & \rm OBr^{-}\; (aq) &+&\rm H_2O\; (l)& \rightleftharpoons & \rm HOBr\; (l)& + & \rm OH^{-}\; (aq) \\ \textbf{I}& 0.200\; \rm M & & & & 0 \; \rm M & & 0\; \rm M \\ \textbf{C} & -x\; \rm M & & & & +x \; \rm M & & +x\; \rm M \\ \textbf{E}& (0.200 + x)\; \rm M & & & & x \; \rm M & & x\; \rm M \end{array}[/tex].

Assume that external factors (such as temperature) stays the same. The [tex]K_\text{eq}[/tex] found at the half-equivalence point should apply here, as well.

[tex]\displaystyle K_\text{eq} = \frac{[\rm HOBr\; (l)]\cdot [\rm OH^{-}\; (aq)]}{[\rm OBr^{-}\; (aq)]}[/tex].

At equilibrium:

[tex]\displaystyle \frac{[\rm HOBr\; (l)]\cdot [\rm OH^{-}\; (aq)]}{[\rm OBr^{-}\; (aq)]} = \frac{x^2}{0.200 + x}[/tex].

Assume that [tex]x[/tex] is much smaller than [tex]0.200[/tex], such that the denominator is approximately the same as [tex]0.200[/tex]:

[tex]\displaystyle \frac{[\rm HOBr\; (l)]\cdot [\rm OH^{-}\; (aq)]}{[\rm OBr^{-}\; (aq)]} = \frac{x^2}{0.200 + x} \approx \frac{x^2}{0.200}[/tex].

That should be equal to the equilibrium constant, [tex]K_\text{eq}[/tex]. In other words:

[tex]\displaystyle \frac{x^2}{0.200} \approx K_\text{eq} = 10^{-6.25}[/tex].

Solve for [tex]x[/tex]:

[tex]x \approx 3.35\times 10^{-4}[/tex].

In other words, the [tex]\rm OH^{-}[/tex] before acid was added was approximately [tex]3.35\times 10^{-4}\; \rm M[/tex], which is the same as [tex]3.35\times 10^{-4}\; \rm mol \cdot L^{-1}[/tex]. Again, assume that [tex]\rm p\mathnormal{K}_\text{w} = 14[/tex]. Calculate the [tex]\rm pH[/tex] of that solution:

[tex]\begin{aligned}\rm pH &= \rm p\mathnormal{K}_\text{w} + \log [\mathrm{OH^{-}}] \approx 10.88\end{aligned}[/tex].

(Rounded to two decimal places.)

Mrs. Wilson leaves her freshly-baked blueberry pie on the windowsill to cool. The delicious fragrance diffuses through the air with a diffusion coefficient of D = 0.2 cm2/s. How long does it take for Dennis to smell the pie in his treehouse 10 meters away? Give your answer in days, without entering the unit.

Answers

Answer:

Poop Buttt.

Explanation:

Amanda is doing a report for her Earth Science class about the four seasons. Which of the following would be an effective scientific model to incorporate in her project? a. A calendar indicating the first days of autumn, winter, spring, and summer b. Four earth models, each with a different tilt to represent the earth’s position relative to the sun, lined up in order of season c. A poster board with pictures of weather characteristic of the four seasons d. A bar graph indicating average high and low temperatures for Amanda’s area in the autumn, winter, spring, and summer Please select the best answer from the choices provided

Answers

Answer:

(B)

Explanation:

edg 2020

The four seasons in earth is originating from the earth's revolution around the sun. Therefore, the most suitable model for Amanda is  Four earth models, each with a different tilt to represent the earth’s position relative to the sun, lined up in order of season.

What are seasons?

Seasons in earth is originating from the difference in the distance from the sun over each time period. Hence, revolution of earth around sun make these seasons.

The time period at which earth comes closer to sun more hot will be earth's surface and we experience summer season. When we far from sun winter season occurs.

Therefore, different season are coming based on the distance of earth from sun at each revolution point. This is also affected by the tilt of earth's in its own axis.

Hence, different earth models with different distance from sun is most suitable model here for Amanda. Thus option B is correct.

To find more about seasons, refer the link below:

https://brainly.com/question/4410000

#SPJ2

What is the magnetic quantum number value for an element with n = 1?

Answers

Answer:

0,

Explanation:

if n was 2, then 1,0,-1

Daniel has a sample of pure copper.its mass is 89.6 grams (g),and its volume is 10 cubic centimeters (cm3). whats the destiny of the sample.

Answers

Answer:

8.96g \ cm3

Explanation:

(89.6\ 10) (g\ cm3) = 8.96g\cm3

Other Questions
Sodium oxide has the chemical formula Na2O. What is the oxidation number of oxygen in this compound? Provide your answer below: ___ Solve the following proportion. x2=57 x=? Calculate the volume of the figure. La suma de dos nmeros diferentes: What are some of the possible pitfalls of owning a credit card? Check all that apply. A Only paying the minimum balance due. B Possible free collision coverage when renting a car. C Paying your bill late. D Establishing a credit rating. E Juggling too many cards. Which European country raised the biggest threat to Spanish dominance in the New world and why Please answer it now in two minutes The surface area of a sphere is 3000 m square units. What is the volume of the sphere to the nearest hunderedth? Milgram's (1963) study on obedience deceived participants by having them think they were shocking someone, but the person was actually only pretending to be shocked. This study would not likely be approved by an Institutional Review Board (IRB) today because the current ethical standards include having the researcher _____________. Hillary has to drive 225 miles in four and a half hours. What should her average speed be in order to arrive on time? 56 mph 45 mph 50 mph 48 mph For what values of a the following expressions are true: |a|=a 8, 18, 11, 15, 5, 4, 14, 9, 19, 1, 7, 17, 6, 16, ? , ?, ?, ?, ? Now, the only numbers used are in the range of 1 to 19. No numbers can be repeated. Now, there is a pattern to the sequence of numbers, and your keen powers of observation will be able to note that the last five numbers used in the sequence will be some combination of 13, 12, 10, 3, and 2. (If youre more into logic brain-busters, a MIT professor called this puzzle the hardest ever.) Any luck? Here are a few hints: The sequence doesnt obey any mathematical rule, and it is not counting any particular group of things. The only way to figure out the problem, according to Spencer, is to think of the numbers as words and write them out. The completed sequence is as follows: 8, 18, 11, 15, 5, 4, 14, 9, 19, 1, 7, 17, 6, 16, 10, 13, 3, 12, 2. Numerically, the sequences order is meaningless. Thats because theyre actually just listed in alphabetical order. While youre in puzzle-mode, a bunch of raccoons solved this ancient Greek riddlecan you figure it out? What is the sine value of pi over 6? negative 1 over 2 1 over 2 negative square root 3 over 2 square root 3 over 2 An article reported that for a sample of 46 kitchens with gas cooking appliances monitored during a one-week period, the sample mean CO2 level (ppm) was 654.16, and the sample standard deviation was 163.7.Required:a. Calculate and interpret a 9596 (two-sided) confidence interval for true average CO2 level in the population of all homes from which the sample was selected. b. Suppose the investigators had made a rough guess of 175 for the value of s before collecting data. What sample size would be necessary to obtain an interval width of 50 ppm for a confidence level of 95%? please help ASAP. Create a quadratic inequality that has this solution: x -7 or x -1. Explain your strategy. A light ray in air strikes water at an angle of incidence equal to 40. If the index of refraction for water is 1.33, what is the angle of refraction? a truck and a car drive uniformly among the expressway from city a to city b. The truck leaves at 09:15 am and arrives at 1:15 pm. The car leaves at 10:00 am and arrives at 12:45 pm. At what times does the car overtake the truck? please help A walking path across a park is represented by the equation y=-3x - 3.Anew path will be built perpendicular to this path. The paths will intersect atthe point (-3,6). Identify the equation that represents the new path. Choose one of the keys to time management and discuss how you can apply it to your daily schedule. a. Don't waste short periods of time. b. Group activities together c. finish one task before starting another task. d. Avoid interruptions. 1.10 The table gives the pH values of a few substances.SubstancepH2Hydrochloric acidApple juice4Water7Ammonia11,5Which substance in the table is an example of a base?A Hydrochloric acidB Apple juiceC WaterD Ammonia