Post Exam Review TCHM-136

Strong acids/bases

100

Is the following acid a strong acid: 

HCl

Yes, HCl is a strong acid.

200

Is the following a strong acid:

HBr

Yes, HBr is a strong acid.

300

Is the following a strong base:

Mg(OH)₂

No, Mg(OH)₂ is not a strong base.

400

Is the following a strong base:

NH₃

No, NH₃ is not a strong base.

500

Is the following a strong base:

Sr(OH)₂

Yes, Sr(OH)₂ is a strong base.

Definitions

100

What is a Brønsted-Lowry acid?

They donate protons (H+). 

200

What is a Brønsted-Lowry base?

They accept protons (H+).

300

What is an Arrhenius acid?

Something that reacts with water to produce H+.

400

What is an Arrhenius base?

A compound that produces hydroxide ions in water.

500

What does it mean to dissociate? Provide an example.

For something to dissociate, it must break up into it's respective ions. 

Definitions Cont.

100

What is a conjugate acid?

A conjugate acid is the result of a base after a H+ is added.

200

What is a conjugate base?

A conjugate base is the result of an acid after a H+ is removed.

300

What is Ka and what does it represent?

Ka stands for the acid dissociation constant and is one of the ways we can label how strong an acid is. Larger Ka means the acid is more likely to dissociate, which also means it is a stronger acid. Smaller Ka means the acid is not likely to dissociate, which also means it is a weaker acid. 

400

What does it mean for something to be amphoteric? Name one of them.

Amphoteric means for something to react as an acid AND base. Water is a very common example. 

500

Bonus points!

Bonus points!

Acid/Base reactions

100

Label the following reaction with acid, base, C. acid, and C. base. 

HCl + H₂O --> H₃O⁺ + Cl^- 

HCl = acid

H₂O = base

H₃O⁺ = C. acid

Cl^- = C. base

200

Label the following reaction with acid, base, C. acid, and C. base.

NH₃ + H₂O --> NH₄⁺ + OH^-

(Reaction is actually reversible)

H₂O = acid

NH₃ = base

NH₄⁺ = C. acid

OH^- = C. base

300

Label the following reaction with acid, base, C. acid, and C. base.

CH₃COOH + H₂O --> CH₃COO^- + H₃O⁺

(Reaction actually reversible)

CH₃COOH = acid

H₂O = base

H₃O⁺ = C. acid

CH₃COO^- = C. base

400

Label the following reaction with acid, base, C. acid, and C. base.

H₂CO₃ + H₂O --> HCO₃^- + H₃O⁺

(Reaction actually reversible)

H₂CO₃ = acid

H₂O = base

HCO₃^- = C. acid

H₃O⁺ = C. base

500

Label the following reaction with acid, base, C. acid, and C. base.

HCO₃^- + H₂O --> H₂CO₃ + OH^-

(Reaction actually reversible)

H₂O = acid

HCO₃^- = base

H₂CO₃ = C. acid

OH^- = C. base

pOH and pH

100

If a specific solution has a pH of 11, what is the pOH?

3

200

If a specific solution has a pH of 1, what is the pOH?

13

300

What is the pH of a 0.37 M NaOH solution?

Roughly 13.57

400

What is the pOH of a 0.55 M HCl solution?

Roughly 13.74

500

What is the pH of a 0.20 M acetic acid (CH₃COOH) solution if Ka = 1.8 x 10^-5?

CH₃COOH (aq) + H₂O (l) --> H₃O⁺ (aq) + CH₃COO^- (aq)

(Reaction is actually reversible)

Roughly 2.72.