You have 100 mL of a solution of benzoic acid in water; the amount of benzoic acid in the solution is estimated to be about 0.30 g. The distribution coefficient of benzoic acid in diethyl ether and water is approximately 10. Calculate the amount of acid that would be left in the water solution after four 20-mL extractions with ether.

Answers

Answer 1

Answer:

0.00370 g

Explanation:

From the given information:

To determine the amount of acid remaining using the formula:[tex]\dfrac{(final \ mass \ of \ solute)_{water}}{(initial \ mass \ of \ solute )_{water}} = (\dfrac{v_2}{v_1+v_2\times k_d})^n[/tex]

where;

v_1 = volume of organic solvent = 20-mL

n = numbers of extractions = 4

v_2 = actual volume of water = 100-mL

k_d = distribution coefficient = 10

[tex]\dfrac{(final \ mass \ of \ solute)_{water}}{0.30 \ g} = (\dfrac{100 \ ml}{100 \ ml +20 \ ml \times 10})^4[/tex]

[tex]\dfrac{(final \ mass \ of \ solute)_{water}}{0.30 \ g} = (\dfrac{100 \ ml}{100 \ ml +200 \ ml})^4[/tex]

[tex]\dfrac{(final \ mass \ of \ solute)_{water}}{0.30 \ g} = (\dfrac{1}{3})^4[/tex]

[tex]\dfrac{(final \ mass \ of \ solute)_{water}}{0.30 \ g} = 0.012345[/tex]

Thus, the final amount of acid left in the water = 0.012345 * 0.30

= 0.00370 g


Related Questions

If 4.00 moles of O2 occupies a volume of 5.0 L at a particular temperature and pressure, what volume will 3.00 moles of oxygen gas occupy under the same condition?

Answers

Answer: Volume occupied by 3.00 moles of oxygen gas under the same condition is 3.75 L.

Explanation:

Given: [tex]n_{1}[/tex] = 4.00 moles,          [tex]V_{1}[/tex] = 5.0 L

[tex]n_{2}[/tex] = 3.00 moles,                 [tex]V_{2}[/tex] = ?

Formula used is as follows.

[tex]\frac{V_{1}}{n_{1}} = \frac{V_{2}}{n_{2}}[/tex]

Substitute the values into above formula as follows.

[tex]\frac{V_{1}}{n_{1}} = \frac{V_{2}}{n_{2}}\\\frac{5.0 L}{4.00 mol} = \frac{V_{2}}{3.00 mol}\\V_{2} = 3.75 L[/tex]

Thus, we can conclude that volume occupied by 3.00 moles of oxygen gas under the same condition is 3.75 L.

21.5g of sodium chloride dissolves in 60g of water at25C. Calculate the concentration of the solution.

Answers

The answer will be:
Solubility of the mixture = 21.5/60 x 25 = 8.96
Hope this helps.

Classify these bonds as ionic, polar covalent, or nonpolar covalent. You are currently in a sorting module. Turn off browse mode or quick nav, Tab to items, Space or Enter to pick up, Tab to move, Space or Enter to drop. Ionic Polar covalent Nonpolar covalent C-O , Mg-F , Cl-Cl

Answers

Answer: The bond present in given compounds is as follows-

Ionic - MgFPolar covalent - CONon-polar covalent - Cl-Cl

Explanation:

A bond formed due to transfer of electrons from one atom to another is called ionic bond.

An ionic bond is always formed between a metal and a non-metal atom.

For example, MgF has metal magnesium and non-metal fluorine. So, an ionic bond is there in the compound MgF.

A compound in which valence electrons are shared between two atoms is called a covalent bond. A covalent bond is always formed between two or more non-metal atoms.

When sharing of electrons occur between atoms of different electronegativity then the bond formed is called a polar covalent bond.

For example, C-O has a polar covalent bond.

When sharing of electrons occur between atoms of same element then bond formed is called non-polar covalent bond.

For example, Cl-Cl is a non-polar covalent bond.

Name an alkene that would yield the alcohol above on hydration. (Submit a single name even if there is more than one correct answer. Ignore double bond stereochemistry.) Name: fill in the blank 75a878faaf91fe7_1 2,3-Dimethylpentane . Specify whether you would use hydroboration/oxidation or oxymercuration.

Answers

Answer:

Enzyme ? ...............

a) If we have a 4.5 L container of CH 10 gas at a temperature of 178 K and a pressure of 0.50 atm, then how many moles of CaHio do
we have?
b) How many grams of C4H1o do we have?

Answers

Answer:

a) 0.15 mol.

b) 8.95 g.

Explanation:

Hello there!

In this case, according to the given information, it is possible for us to infer this problem is solved by using the ideal gas equation:

[tex]PV=nRT[/tex]

And proceed as follows:

a) Here, we solve for the moles, n,  as follows:

[tex]n=\frac{PV}{RT} \\\\n=\frac{0.50atm*4.5L}{0.08206\frac{atm*L}{mol*K}*178K} \\\\n=0.15mol[/tex]

b) for the calculation of the mass, we recall the molar mass of butane, 58.12 g/mol, to obtain:

[tex]0.15mol*\frac{58.12g}{1mol} =8.95g[/tex]

Regards!

Classify each phrase according to whether it applies to photophosphorylation, oxidative phosphorylation, or both
Photophosphorylation Oxidative phosphorylation Both
1. occurs in plants produces ATP
2. occurs in chloroplasts
3. occurs in mitochondria
4. involves a larger electrical component
5. involves a smaller electrical component
6. involves a proton gradient

Answers

Answer:

1. Both

2. Phosphorylation

3. Both

4. Phosphorylation

5. Oxidative.

6. Both

Explanation:

Phosphorylation only occurs in chloroplast and it involves larger electrical component. Both Phosphorylation and oxidative occurs in mitochondria and it involves proton gradient. They occur in plants to produce ATP. Oxidative involves in smaller electrical component.

Photophosphorylation is a process that captures the solar energy from the sun to transform it into chemical energy. It occurs in the chloroplast of a plant cell.

What are photophosphorylation and oxidative phosphorylation?

Photophosphorylation is a process of converting solar energy from the sun to ATP needed by plants and other organisms for cellular function and activity. This process takes place in the chloroplast of the plant cell and requires electrical components.

Oxidative Phosphorylation is the process of producing ATP with the help of oxygen and enzymes hence, occurs in aerobic cells. It does not need a larger electrical component.

Both phosphorylation and oxidative phosphorylation occurs in the mitochondria of plants cells and involves a proton gradient for the formation of ATP.

Therefore, oxidative phosphorylation option 5. involves a smaller electrical component, phosphorylation option 2. occurs in the chloroplast, and option 4. needs a larger electrical component.

Learn more about phosphorylation here:

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If we have 1.23 mol of NaOH in solution and 0.85 mol of Cl2 gas is available to react, which one is the limiting reactant? Give your reason.​

Answers

Answer:

NaOH is the limiting reactant.

Explanation:

Hello there!

In this case, since the reaction taking place between sodium hydroxide and chlorine has is:

[tex]NaOH+Cl_2\rightarrow NaCl+NaClO+H_2O[/tex]

Which must be balanced according to the law of conservation of mass:

[tex]2NaOH+Cl_2\rightarrow NaCl+NaClO+H_2O[/tex]

Whereas there is a 2:1 mole ratio of NaOH to Cl2, which means that the moles of the former that are consumed by 0.85 moles of the latter are:

[tex]n_{NaOH}=0.85molCl_2*\frac{2molNaOH}{1molCl_2}\\\\n_{ NaOH}=1.7molNaOH[/tex]

Therefore, since we just have 1.23 moles out of 1.70 moles of NaOH, we infer this is the limiting reactant.

Regards!

At a constant temperature of 30 °C, an ideal gas occupies 2.78 Liters at a pressure of 1.27 atm. What will be the volume (L) at a pressure of 3.95 atm?

Answers

Answer:

[tex]V_2=0.894L[/tex]

Explanation:

Hello there!

In this case, according to the given information, it turns out possible for us to solve this problem by using the Boyle's law for an inversely proportional relationship between pressure and volume at constant temperature, as described in the problem statement:

[tex]P_2V_2=P_1V_1[/tex]

Thus, we solve for V2, final volume, to obtain the following result:

[tex]V_2=\frac{P_1V_1}{P_2} \\\\V_2=\frac{1.27atm*2.78L}{3.95atm}\\\\V_2=0.894L[/tex]

Regards!

Chemosynthesis and photosynthesis are both processes that produce food.

True or false?

Answers

Answer:

true

Explanation:

probably true

Rank the solutions below in order of increasing acidity. (Drag and drop into the appropriate area)
0.01 M CH3COOH
0.1 M NaOH
0.01 M H2SO4
3 M NH3
0.1 M HCl

Answers

Answer:

0.1 M NaOH, 3 M NH3, 0.01 M CH3COOH, 0.01 M H2SO4, 0.1 M HCl

Explanation:

Strong acids are more acids than weak acids. In the same way, strong bases are more basic than weak bases that are in the same concentration.

Then, the more concentrated acid or base will be more acidic or basic.

CH3COOH. Weak acid

NaOH. Strong base

H2SO4. Strong acid

NH3. Weak base.

HCl. Strong acid

The less acid (More basic):

0.1 M NaOH, 3 M NH3, 0.01 M CH3COOH, 0.01 M H2SO4, 0.1 M HCl

Strong base, weak base, weak acid, diluted strong acid, undiluted strong acid

Acetylide ions react with aldehydes and ketones to give alcohol addition products.

a. True
b. False

Answers

Answer:

a

Explanation:

For the equilibrium that exists in an aqueous solution of nitrous acid (HNO2, a weak acid), the equilibrium constant expression is: _________

a. K = [ H+] [NO2-] / [HNO2]
b. K = [ H+] [N] [O]2 / [HNO2]
c. K = [ H+] [NO2-] / [HNO2]
d. K = [H+]2 [NO2-] / [HNO2]
e. None of these

Answers

Answer: For the equilibrium that exists in an aqueous solution of nitrous acid (HNO2, a weak acid), the equilibrium constant expression is K = [ H+] [NO2-] / [HNO2].

Explanation:

An expression that depicts the ratio of products and reactants raised to the power of their coefficients at equilibrium is called equilibrium constant.

An equilibrium constant is denoted by the symbol 'K'.

For example, the dissociation of nitrous acid in aqueous solution is as follows.

[tex]HNO_{2} \rightleftharpoons H^{+} + NO^{-}_{2}[/tex]

Hence, its expression for equilibrium constant is as follows.

[tex]K = \frac{[H^{+}][NO^{-}_{2}]}{[HNO_{2}]}[/tex]

Thus, we can conclude that for the equilibrium that exists in an aqueous solution of nitrous acid (HNO2, a weak acid), the equilibrium constant expression is K = [ H+] [NO2-] / [HNO2].

Obtain 2 test tubes. 2. Add 2 mL of animal blood plasma into the first test tube a. Use a pH test strip to measure the pH of the blood plasma. ______

Answers

Answer:

7.4

Explanation:

Plasma proteins are part of the buffer systems of blood plasma. Plasma contains both positively and negatively charged amino and carboxyl groups. These compounds' charged portions can attract and link hydrogen(H) and hydroxyl ions(OH-), therefore act as buffers.

Plasma serves as a weak and ineffective buffer. The pH of a buffer should always be around 7.4 which is nearly neutral. As such we may deduce from the first experimental observation that there is no change in pH.

1) 7.269 moles of oxygen gas are used in combusting butane (C H..). How many moles of carbon dioxide
gas are produced? You must start with a balanced chemical equation. Start with a balanced equation

Answers

Explanation:

C4H10 + 13/2O2 ---------> 4CO2 + 5H2O

so u can work out the amount of moles by doing

moles=mass/mr

mr of C4H10 is 12 × 4 + 10 =58

=7.269/58

= 0.125moles

Then u can use the molar ratio which is

6.5:4

0.125 ÷6.5 × 4 = 0.0769moles

hope this helps:)

Define pure substance. How is it classified on the basid of chemical properties?​

Answers

Answer:

if it is pure, the substances is either an element or a compound. if a substance is not chemically pure, it is either a heterogeneous mixture or a homogeneous mixture. if its composition is uniform throughout, it is a homogeneous.

The information below describes a redox reaction.
Ag+ (aq) + Al(s) — Ag(s) + Al3+ (aq)
Ag+ (aq) + -> Ag(s)
Al(s)->A3+ (aq) + 3e-
What is the coefficient of silver in the final, balanced equation for this reaction?

Answers

Answer:

Al°(s)  + 3Ag⁺(aq) => Al⁺³(aq) + 3Ag(s)

Explanation:

Oxidation:                            Al°(s) =>   Al⁺³(aq) + 3e⁻

Reduction:           3Ag⁺(aq) + 3e⁻ => 3Ag°(s)

_________________________________________

Net Rxn:           Al°(s)  + 3Ag⁺(aq) => Al⁺³(aq) + 3Ag(s)

One mole of neutral aluminum atoms (Al°(s)) undergo oxidation delivering 3 moles  of electrons to 3 moles silver ions (3Ag⁺³(aq)) that are reduced to 3 moles of neutral silver atoms (3Ag°(s)) in basic standard state 25°C; 1atm.

A balanced equation obeys the law of conservation of mass. According to the law of conservation of mass, mass can neither be created nor be destroyed. The coefficient of silver is 3.

What is a balanced equation?

A balanced chemical equation can be defined as the chemical equation in which the number of reactants and products on both sides of the equation are equal. The amount of reactants and products on both sides of the equation will be equal in a balanced chemical equation.

The numbers which are used to balance the chemical equation are called the coefficients. The coefficients are the numbers which are added in front of the formula.

The balanced chemical equation for the given redox reaction is given as:

Al (s) + 3 Ag⁺ (aq)  → Al³⁺ (aq) + 3Ag (s)

Thus the coefficient of silver is 3.

To know more about balanced equation, visit;

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Atoms are found to move from one lattice position to another at the rate of 300,000 jumps/s at 500 0C when the activation energy for their movement is 10,000 cal/mol. Calculate the jump rate at 400 0C.

Answers

Answer:

1

Explanation:

1

At a fixed volume, a four-fold increase in the temperature of a gas will lead to _______ in pressure.
Question 2 options:

A)

no change

B)

a two-fold decrease

C)

a four-fold decrease

D)

a four-fold increase

Answers

Answer:

D) a four-fold increase

Explanation:

According to Gay-Lussac's law, which states that the pressure of a given amount of gas is directly proportional to the temperature at a constant volume, the pressure increases with an increase in temperature.

According to this question, at a fixed volume, a four-fold increase in the temperature of a gas will lead to a four-fold increase in the pressure as well.

You dissolve 14 g of Mg(NO3)2 in water and dilute to
750 mL. What is the molarity of this solution?

Answers

Answer:

0.127M

Explanation:

Molarity of a solution = number of moles (n) ÷ volume (V)

Molar mass of Mg(NO3)2 = 24 + (14 + 16(3)}2

= 24 + {14 + 48}2

= 24 + 124

= 148g/mol

Using the formula, mole = mass/molar mass, to convert mass of Mg(NO3)2 to mole

mole = 14g ÷ 148g/mol

mole = 0.095mol

Volume = 750mL = 750/1000 = 0.75L

Molarity = 0.095mol ÷ 0.75L

Molarity = 0.127M

You have 4 litres of a 3.0 mol/L solution of NaCl in a chemical store room.
How many moles of NaCl are present?

Answers

Answer:

12

Explanation:

nNaCl= 4x3=12

4. Complete the following equations:
CuCl2 + Na2CO3 → 2 NaCl +............
FeSO4 + BaCl2 →


Cu(NO3)2 + CaCO3

Answers

Answer:

2NaCl + CuCO3

FeCl2 + BaSO4

CuCO3 + Ca(NO3)2

Explanation:

Presumably this is a double replacement reaction.

A+B + C+D A+D + C+B

It seems I may be wrong so please try to work out the problem yourself to double check, keeping in mind the charges of each compound.

I need the answer please

Answers

Answer:

the answer is the first one

Na+

La función de la levadura en quimica

Answers

Explanation:

las levaduras son pequeños organismos unicelulares que se alimentan de azúcares simples y los descomponen en dióxido de carbono, alcohol (etanol, específicamente), moléculas de sabor y energía. El proceso se conoce como fermentación.

This reaction was at equilibrium when 0.2 atm of iodine gas was pumped into the container, what happened to the equilibrium and the partial pressures of the gases

Answers

Answer:

Q was < K. Partial pressure of hydrogen decreased, iodine increased

Explanation:

After iodine was added the Q was [Select] K so the reaction shifted toward the Products [Select] ,The partial pressure of hydrogen [Select], Iodine [Select] |,and hydrogen iodide Decreased

Based on the equilibrium:

H2(g) + I2(g) ⇄ 2HI(g)

K of equilibrium is:

K = [HI]² / [H2] [I2]

Where [] are concentrations at equilibrium

And Q is:

Q = [HI]² / [H2] [I2]

Where [] are actual concentrations of the reactants.

When the reaction is in equilibrium, K=Q.

But as [I2] is increased, Q decreases and Q was < K

The only concentration that increases is [I2], doing partial pressure of hydrogen decreased, iodine increased

What is the colour of red cabbage in vinegar?​

Answers

Answer:

When red cabbage is treated with an acid or a base, it produces anthocyanin, a water-soluble pigment that changes color. In acidic situations with a pH less than 7, the pigment turns red, whereas in alkaline (basic) situations with a pH more than 7, the pigment turns bluish-green.

Explanation:

When in vinegar in turns to a pinkish/red due to it being in the presence of an acidic substance.

What is the meaning of beaker?

Answers

Answer:

a  lipped cylindrical glass container for laboratory use

Explanation:

Can someone help me with this one

Answers

Answer:

Easy my dude let me help you out

A.In

B.27

C.73

D.49

E.56

F.56

G.114

H.180

Also with protons and electrons they equal the same atomic number

Phosphate buffers are commonly used in biological research. If a small amount of strong acid is added to a buffer solution that is 0.700 M H3PO4 and 0.700 M KH2PO4, which of the following statements is true?
A) [H3PO4] will increase, [KH2PO4] will decrease, and pH will slightly decrease.
B) [H3PO4] will increase, [KH2PO4] will decrease, and pH will not change.
C) [H3PO4] will decrease, [KH2PO4] will increase, and pH will slightly decrease.
D) [H3PO4] will decrease, [KH2PO4] will increase, and pH will slightly increase.
E) [H3PO4] will increase, [KH2PO4] will decrease, and pH will slightly increase.
F) [H3PO4] will decrease, [KH2PO4] will increase, and pH will not change

Answers

Answer:

A) [H3PO4] will increase, [KH2PO4] will decrease, and pH will slightly decrease.

Explanation:

A buffer is a solution which resists changes to its pH when a small amount of acid or base is added to it.

Buffers consist of a weak acid (HA) and its conjugate base (A–) or a weak base and its conjugate acid. Weak acids and bases do not completely dissociate in water, and instead exist in solution as an equilibrium of dissociated and undissociated species. When a small quantity of a strong acid is added to a buffer solution, the conjugate base, A-, reacts with the hydrogen ions from the added acid to form the weak acid and a salt thereby removing the extra hydrogen ions from the solution and keeping the pH of the solution fairly constant. On the other hand, if a small quantity of a strong base is added to the buffer solution, the weak acid dissociates further to release hydrogen ions which then react with the hydroxide ions of the added base to form water and the conjugate base.

For example, if a small amount of strong acid is added to a buffer solution that is 0.700 M H3PO4 and 0.700 M KH2PO4, the following reaction is obtained:

KH₂PO₄ + H+ ----> K+ + H₃PO₄

Therefore, [H₃PO₄] will increase, [KH₂PO₄] will decrease, and pH will slightly decrease.:

38. Consider the following equilibrium:
2CO(g) + O2(g) =2CO2
Keg=4.0 x 10-10
What is the value of Key for 2CO2(g) + 2COR + O2g) ?​

Answers

Answer:

[tex]Key=2.5x10^{-9}[/tex]

Explanation:

Hello there!

In this case, according to the given information, it turns out possible for us to calculate the equilibrium constant value for the reverse reaction:

[tex]2CO_2(g) \rightleftharpoons 2CO(g) + O_2(g)[/tex]

By knowing that the equilibrium expression is actually:

[tex]Key =\frac{[CO]^2[O_2]}{[CO_2]^2} =\frac{1}{Keg}[/tex]

Thus, we plug in and solve for the inverse of Keq to obtain Key as follows:

[tex]Key =\frac{1}{4.0x10^{-10}}\\\\Key=2.5x10^{-9}[/tex]

Regards!

I need to summarize each type of radioactive decay.

Answers

Answer:

1. alpha -  decreased mass by 4  - decrease atomic number by 2

2. beta electron - no change - increase by 1

3 - beta positron - no change - decrease by 1

4. gamma - no change - no change

5. electron capture - no change - decrease by 1

Explanation:

There are five main types of radioactive decay, a process where the nucleus loses energy by emitting radiation, these radiation or type of radioactive decay are alpha particles, beta particles, positron or beta positron, gamma particles and electron capture.

The effect of these particles causes a change in the number of subatomic which leads to different atomic mass and atomic numbers after the decay -

1. alpha -  decreased mass by 4  - decrease the atomic number by 2

2. beta electron - no change - increase by 1

3 - beta positron - no change - decrease by 1

4. gamma - no change - no change

5. electron capture - no change - decrease by 1

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