Question 1

In the following reaction the unshaded spheres represent H atoms.  
-Identify the Br∅nsted-Lowry acid/base conjugate pairs.

Accepted Answer

A) (1)/(2)and (3)/(4) 
B) (1)/(3)and (2)/(4) 
C) (1)/(4)and (2)/(3) 
A) (1)/(2)and (3)/(4) 
B) (1)/(3)and (2)/(4) 
C) (1)/(4)and (2)/(3)

Question 2

A 0.50 M solution of a weak acid HA has the same pH as a 0.075 M solution of HCl.Calculate the Ka for HA.

Accepted Answer

A) 0.50 
B) 0.075 
C) 0.1324 
D) 0.01125 
A) 0.50 
B) 0.075 
C) 0.1324 
D) 0.01125

Question 3

What is the geometric shape of the hydrated proton;that is,the hydronium ion H3O+?

Accepted Answer

A) angular 
B) trigonal pyramidal 
C) trigonal planar 
D) tetrahedral 
A) angular 
B) trigonal pyramidal 
C) trigonal planar 
D) tetrahedral

Question 4

What is the pH of a solution prepared by mixing 100.00 mL of 0.025 M Ca(OH)2 with 50.00 mL of 0.080 M LiOH? Assume that the volumes are additive.

Accepted Answer

A) 12.67 
B) 12.78 
C) 12.95 
D) 13.25 
A) 12.67 
B) 12.78 
C) 12.95 
D) 13.25

Question 5

What is the strongest acid among the following?

Accepted Answer

A) CH3CO2H 
B) ClCH2CO2H 
C) Cl2CHCO2H 
D) Cl3CCO2H 
A) CH3CO2H 
B) ClCH2CO2H 
C) Cl2CHCO2H 
D) Cl3CCO2H

Question 6

From the following chemical reactions determine the relative Br∅nsted-Lowry base strengths (strongest to weakest). 2 NaH(s)+ H2O(l)→ 2 NaOH + H2(g)
NH3(aq)+ H2O(l)⇌ NH4+(aq)+ OH-(aq)

Accepted Answer

A) H- > OH- > NH3 
B) H- > NH3 > OH- 
C) OH-> H- > NH3 
D) OH- > NH3 > H- 
A) H- > OH- > NH3 
B) H- > NH3 > OH- 
C) OH-> H- > NH3 
D) OH- > NH3 > H-

Question 7

What is the hydronium ion concentration of an acid rain sample that has a pH of 3.25?

Accepted Answer

A) 1.78 × 10-11 M 
B) 5.62 × 10-4 M 
C) 3.25 M 
D) 10.75 M 
A) 1.78 × 10-11 M 
B) 5.62 × 10-4 M 
C) 3.25 M 
D) 10.75 M

Question 8

What is the identity of M in the hydrate M(H2O)6n+ that has the 0.10 M solution with the lowest pH?

Accepted Answer

A) Li+ 
B) Na+ 
C) Mg2+ 
D) Al3+ 
A) Li+ 
B) Na+ 
C) Mg2+ 
D) Al3+

Question 9

Equal volumes of 0.10 M NH3 (Kb = 1.8 × 10-5)and 0.10 M HCN (Ka = 4.9 × 10-10)are mixed together.Will the resulting solution be acidic,basic,or neutral?

Accepted Answer

A) acidic 
B) basic 
C) neutral 
D) insufficient information to solve 
A) acidic 
B) basic 
C) neutral 
D) insufficient information to solve

Question 10

In the reaction between NO2 and H2O that produces HNO3,the Lewis acid is ________ and the Lewis base is ________.

Accepted Answer

Question 11

The number of waters of hydration in the hydrate proton H11O5+ is ________.

Accepted Answer

Question 12

Which of the following species cannot act as a Lewis base?

Accepted Answer

A) O2- 
B) CH4 
C) H2O 
D) NH3 
A) O2- 
B) CH4 
C) H2O 
D) NH3

Question 13

In order for the reaction A- + H2CO3 ⇌ HA + HCO3- to have an equilibrium constant Kc a of HA must be ________ (greater,less)than the Ka of H2CO3.

Accepted Answer

Question 14

The following pictures represent equal volumes of aqueous solutions of three acids HA (A = X,Y,or Z);water molecules have been omitted for clarity.  
-Arrange the conjugate bases (A- = X-,Y-,or Z-)in order of increasing base strength.

Accepted Answer

A) Z- - - 
B) Y- - - 
C) Z- - - 
D) X- - - 
A) Z- - - 
B) Y- - - 
C) Z- - - 
D) X- - -

Question 15

The pH of a 0.055 M KOH solution is ________.

Accepted Answer

The answer of The pH of a 0.055 M KOH...

Question 16

What is the pH of a 2.4 M pyridine solution that has Kb = 1.9 × 10-9? The equation for the dissociation of pyridine is C5H5N(aq)+ H2O(l)⇌ C5H5NH+(aq)+ OH-(aq).

Accepted Answer

A) 4.17 
B) 8.72 
C) 9.83 
D) 10.83 
A) 4.17 
B) 8.72 
C) 9.83 
D) 10.83

Question 17

An acidic solution at 25°C will have a hydronium ion concentration ________ and a pH value ________.

Accepted Answer

A) [H3O+] > 1 × 10-7 M,pH > 7.00 B) [H3O+] > 1 × 10-7 M,pH 3O+] -7 M,pH > 7.00 D) [H3O+] -7 M,pH < 7.00 A) [H3O+] > 1 × 10-7 M,pH > 7.00 B) [H3O+] > 1 × 10-7 M,pH 3O+] -7 M,pH > 7.00 D) [H3O+] -7 M,pH < 7.00

Question 18

The following pictures represent aqueous solutions of three acids HA (A = X,Y,or Z);water molecules have been omitted for clarity.  
-Which acid,if any,is a strong acid?

Accepted Answer

A) All are strong acids. 
B) HX and HZ 
C) HY 
D) None are strong acids. 
A) All are strong acids. 
B) HX and HZ 
C) HY 
D) None are strong acids.

Question 19

-Of the elements indicated on the periodic table shown above,which forms the strongest oxoacid acid with the formula H2XO3 or HXO3,where X = A,B,C,or D?

Accepted Answer

A) A 
B) B 
C) C 
D) D 
A) A 
B) B 
C) C 
D) D

Question 20

Which of the following salts are acidic?

Accepted Answer

A) LiCl,NaCl,KCl 
B) NH4Cl,CuCl2,AlCl3 
C) NaCH3CO2,LiCH3CO2,RbCH3CO2 
D) KCl,NH4Cl,Na2CO3 
A) LiCl,NaCl,KCl 
B) NH4Cl,CuCl2,AlCl3 
C) NaCH3CO2,LiCH3CO2,RbCH3CO2 
D) KCl,NH4Cl,Na2CO3

Exam 15: Aqueous Equilibria: Acids and Bases

In the following reaction the unshaded spheres represent H atoms. -Identify the Br∅nsted-Lowry acid/base conjugate pairs.

A 0.50 M solution of a weak acid HA has the same pH as a 0.075 M solution of HCl.Calculate the Ka for HA.

What is the geometric shape of the hydrated proton;that is,the hydronium ion H3O+?

What is the pH of a solution prepared by mixing 100.00 mL of 0.025 M Ca(OH)2 with 50.00 mL of 0.080 M LiOH? Assume that the volumes are additive.

What is the strongest acid among the following?

From the following chemical reactions determine the relative Br∅nsted-Lowry base strengths (strongest to weakest). 2 NaH(s)+ H2O(l)→ 2 NaOH + H2(g) NH3(aq)+ H2O(l)⇌ NH4+(aq)+ OH-(aq)

What is the hydronium ion concentration of an acid rain sample that has a pH of 3.25?

What is the identity of M in the hydrate M(H2O)6n+ that has the 0.10 M solution with the lowest pH?

Equal volumes of 0.10 M NH3 (Kb = 1.8 × 10-5)and 0.10 M HCN (Ka = 4.9 × 10-10)are mixed together.Will the resulting solution be acidic,basic,or neutral?

In the reaction between NO2 and H2O that produces HNO3,the Lewis acid is ________ and the Lewis base is ________.

The number of waters of hydration in the hydrate proton H11O5+ is ________.

Which of the following species cannot act as a Lewis base?

In order for the reaction A- + H2CO3 ⇌ HA + HCO3- to have an equilibrium constant Kc < 1,the Ka of HA must be ________ (greater,less)than the Ka of H2CO3.

The following pictures represent equal volumes of aqueous solutions of three acids HA (A = X,Y,or Z);water molecules have been omitted for clarity. -Arrange the conjugate bases (A- = X-,Y-,or Z-)in order of increasing base strength.

The pH of a 0.055 M KOH solution is ________.

What is the pH of a 2.4 M pyridine solution that has Kb = 1.9 × 10-9? The equation for the dissociation of pyridine is C5H5N(aq)+ H2O(l)⇌ C5H5NH+(aq)+ OH-(aq).

An acidic solution at 25°C will have a hydronium ion concentration ________ and a pH value ________.

The following pictures represent aqueous solutions of three acids HA (A = X,Y,or Z);water molecules have been omitted for clarity. -Which acid,if any,is a strong acid?

-Of the elements indicated on the periodic table shown above,which forms the strongest oxoacid acid with the formula H2XO3 or HXO3,where X = A,B,C,or D?

Which of the following salts are acidic?

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A 0.50 M solution of a weak acid HA has the same pH as a 0.075 M solution of HCl.Calculate the K_a for HA.

What is the geometric shape of the hydrated proton;that is,the hydronium ion H₃O⁺?

What is the pH of a solution prepared by mixing 100.00 mL of 0.025 M Ca(OH)₂ with 50.00 mL of 0.080 M LiOH? Assume that the volumes are additive.

From the following chemical reactions determine the relative Br∅nsted-Lowry base strengths (strongest to weakest). 2 NaH(s)+ H₂O(l)→ 2 NaOH + H₂(g) NH₃(aq)+ H₂O(l)⇌ NH₄⁺(aq)+ OH^-(aq)

What is the identity of M in the hydrate M(H₂O)₆ⁿ⁺ that has the 0.10 M solution with the lowest pH?

Equal volumes of 0.10 M NH₃ (K_b = 1.8 × 10^-5)and 0.10 M HCN (K_a = 4.9 × 10^-10)are mixed together.Will the resulting solution be acidic,basic,or neutral?

In the reaction between NO₂ and H₂O that produces HNO₃,the Lewis acid is and the Lewis base is .

The number of waters of hydration in the hydrate proton H₁₁O₅⁺ is ________.

In order for the reaction A^- + H₂CO₃ ⇌ HA + HCO₃^- to have an equilibrium constant K_c < 1,the K_a of HA must be ________ (greater,less)than the K_a of H₂CO₃.

The following pictures represent equal volumes of aqueous solutions of three acids HA (A = X,Y,or Z);water molecules have been omitted for clarity. -Arrange the conjugate bases (A^- = X^-,Y^-,or Z^-)in order of increasing base strength.

What is the pH of a 2.4 M pyridine solution that has K_b = 1.9 × 10^-9? The equation for the dissociation of pyridine is C₅H₅N(aq)+ H₂O(l)⇌ C₅H₅NH⁺(aq)+ OH^-(aq).

An acidic solution at 25°C will have a hydronium ion concentration and a pH value .

-Of the elements indicated on the periodic table shown above,which forms the strongest oxoacid acid with the formula H₂XO₃ or HXO₃,where X = A,B,C,or D?