AP Chem Unit 2 Review

Unit 1

100

Determine the correct number of sig figs for the following:

1) 32.567 + 135.0 + 1.4567 = 

2) 246.24 + 238.278 + 98.3 = 

3) 81.04 x 0.010 = 

4) 28.367 / 3.74 = 

1) 169.0

2) 582.8

3) 0.81

4) 7.58

(25 points each)

200

This metric system prefix means 10^-6, and is abbreviated with the Greek letter μ. 

What is micro?

300

This law states that if two elements, A and B, form more than one compound, the masses of B that combine with a given mass of A are in the ratio of small whole numbers.

What is the Law of Multiple Proportions?

400

These molecules are known for their catchy mnemonic and are classified as diatomic molecules.

What are hydrogen, oxygen, fluorine, bromine, iodine, nitrogen, and chlorine?

500

A major textile dye manufacturer developed a new yellow dye. The dye has a percent composition of 75.95% C, 17.72% N, and 6.33% H by mass with a molar mass of about 240 g/mol. Determine the empirical and molecular formula of the dye.

Empirical: C₅H₅N

Molecular: C₁₅H₁₅N₃

Molarity Problems

100

What is the molarity of a solution that was prepared by dissolving 14.2 g of NaNO₃ in enough water to make 350 mL of solution?

0.477 M

200

How many grams of NaBr would be needed to prepare 700 ml of 0.230 M NaBr solution?

16.6 g NaBr

300

It takes 83 mL of a 0.45 M NaOH solution to neutralize 235 mL of an HCl solution. What is the concentration of the HCl solution?

0.16 M HCl

400

Titration reveals that 11.6 mL of 3.0 M sulfuric acid are required to neutralize the sodium hydroxide in 25.00 mL of NaOH solution. What is the molarity of the NaOH solution?

2.8 M NaOH

500

Determine the molarity for each of the following solutions:

1) 0.444 mol of CoCl₂ in 0.654 L of solution

2) 1.8 × 10⁴ mg of HCl in 0.075 L of solution

3) 0.2074 g of calcium hydroxide, Ca(OH)₂, in 40.00 mL of solution

4) 10.5 kg of Na₂SO₄ in 18.60 L of solution

5) 7.0 × 10⁻³ mol of I₂ in 100.0 mL of solution

1) 0.679 M

2) 6.6 M

3) 0.06998 M

4) 3.98 M

5) 0.070 M

(100 points each)

Vocab

100

Defined as homogeneous mixtures of two or more pure substances.

What are solutions?

200

This category is known for having HCl, HNO₃, H₂SO₄, HBr, HI, HClO₄, and HClO₃.

What are strong acids?

300

Two terms:

• a substance that dissociates into ions when dissolved in water.

• a substance that may dissolve in water, but it does not dissociate into ions when it does so.

What is an electrolyte?

What is a non-electrolyte?

(100 points each)

400

This pair is known for increasing the concentration of H⁺ and OH^- when dissolved in water.

What are acids and bases?

500

These substances are able to act as either an acid or a base, depending on what it is combined with (for example, H₂O).

What are amphoteric substances?

Reactions

100

Balance each of the following chemical equations:

a) Mg (s) + HCl (aq) --> MgCl₂ (aq) + H₂(g)

b) NH₄NO₃ (s) --> N₂ (g) + O₂ (g) + H₂O (l)

a) Mg (s) + 2HCl (aq) --> MgCl₂ (aq) + H₂(g)

b) 2NH₄NO₃ (s) --> 2N₂ (g) + O₂ (g) + 4H₂O (l)

200

This type of reaction appears as though the ions in the reactant compounds exchange, or transpose, ions, as seen in the equation below.

AgNO₃(aq) + KCl(aq) ⎯→ AgCl(s) + KNO₃(aq)

What are metathesis/exchange/double replacement reactions?

300

Create a balanced equation: 

Aqueous solutions of magnesium chloride and sodium hydroxide react to produce solid magnesium hydroxide and aqueous sodium chloride. What kind of reaction is this?

MgCl₂ (aq) + 2NaOH (aq) --> Mg(OH)₂ (s) + 2NaCl (aq)

Double replacement

(175 points and 125 points)

400

Nickel (III) chloride + potassium phosphate (double replacement)

a) Write a balanced equation for the reactants given. Include the physical states for all reagents: Assume that all reactions are in water.

c) Write a total ionic equation

d) Write the net-ionic equation

a) NiCl₃(aq) + K₃PO₄(aq) ---> NiPO₄(s) + 3KCl(aq)

b) Ni³⁺(aq) + 3Cl^-(aq) + 3K⁺(aq)+ PO₄^-3(aq)-->NiPO₄(s) + 3 Cl^-(aq) + 3K⁺(aq)

c) Ni³⁺(aq) + PO₄^-3(aq) ---> NiPO₄(s)

500

These 5 types of reactions have been discussed heavily throughout the beginning of the year.

What are double displacement, single replacement, combustion, synthesis, and decomposition?

Misc.

100

This group is known for its soluble ions, without exception.

What are Group 1/alkali metals?

200

This polyatomic ion, while usually soluble, is known to be insoluble with Ca⁺², Sr⁺², Ba⁺², Ag⁺, Hg₂⁺², and Pb⁺².

What are sulfates?

300

List these metals in the order of their reactivity: Lithium, Platinum, Hydrogen, Chromium, Calcium

(highest to lowest)

Lithium, Calcium, Chromium, Hydrogen, Platinum

400

Assign oxidation numbers to the following:

1) sulfur in H₂SO₄

2) phosphorus in PO₄^-3

3) nitrogen in HNO₃

4) carbon in CH₂Cl₂

1) 6

2) 5

3) 5

4) 0

(100 points each)

500

Name the following acids:

a) HBr

b) H₂SO₃

Give the formula for the following acids:

c) nitrous acid

d) phosphoric acid

a) hydrobromic acid

b) sulfurous acid

c) HNO₂

d) H₃PO₄

(125 points each)