Practice Problems for CHE 117

Limiting Reagent Practice Problems

Consider the following reaction. Given 10.0 grams of methane (CH4) and 10.0 grams of oxygen (O2), how much carbon dioxide (CO2) can form?
CH4      +      2 O2      reaction arrow       2 H2O      +      CO2

6.875 grams of carbon dioxide (CO2) can form. Oxygen is the limiting reagent.

Consider the following reaction. Given 150 g of chlorine (Cl2) and 100 grams of sodium (Na), how much sodium chloride (NaCl) can form?
2 Na      +      Cl2      reaction arrow       2 NaCl

247 grams of sodium chloride (NaCl) can form. Chlorine (Cl2) is the limiting reagent.

Related problems in your textbook, Chapter 8: 7, 8, 42, 43, 44, 45, 46

Neutralization Practice Problems

Predict the products for each of the following reactions. Be careful to get the correct formula for each product.

KOH      +      H2SO4      reaction arrow       K2SO4      +      H2O     

H3PO4      +      NaOH      reaction arrow       Na3PO4      +      H2O     

HNO3      +      Mg(OH)2      reaction arrow       Mg(NO3)2      +      H2O     

HCl      +      Ca(OH)2      reaction arrow       CaCl2      +      H2O     

Similar problems in Chapter 9 of your textbook: 15, 16, 17, 26

Oxidation Reduction Practice Problems

Identify what is oxidized and what is reduced.
Identify the oxidizing agent and the reducing agent.

CH4      +      2 O2      reaction arrow       2 H2O      +      CO2
carbon (CH4) is oxidized
oxygen is reduced
The oxidizing agent is oxygen.
The reducing agent is methane (CH4).

2 Al2O3      +      3 C      reaction arrow       4 Al      +      3 CO2
aluminum is reduced
carbon is oxidized
The oxidizing agent is Al2O3.
The reducing agent is carbon.

4 Fe      +      3 O2      reaction arrow       2 Fe2O3
Iron (Fe) is oxidized.
Oxygen is reduced.
The oxidizing agent is oxygen.
The reducing agent is zinc.

2 Zn      +      O2      reaction arrow       2 ZnO
Zinc is oxidized.
Oxygen is reduced.
The oxidizing agent is oxygen.
The reducing agent is zinc.

FeCl2      +      Zn      reaction arrow       ZnCl2      +      Fe
Iron (Fe) is reduced.
Zinc is oxidized.
The reducing agent is zinc.
The oxidizing agent is FeCl2.

2 Cu      +      O2      reaction arrow 2 CuO
Copper is oxidized.
Oxygen is reduced
The reducing agent is copper.
The oxidizing agent is oxygen.

Related problems in Chapter 10 of your textbook: 3, 8, 9, 12, 13, 14

pH Problems

Determine the pH for each of the following solutions.

1.0 x 10-5 M HNO3 5.00
0.0342 M NaOH 12.53
1.52 x 10-4 M HCl 3.82
acetic acid with [H3O+] = 3.62 x 10-3 2.44
ammonia solution with [-OH] = 4.6 x 10-5 9.66

Related problems in Chapter 9 of your textbook: 34, 35, 36

Determine the [H3O+] for solutions with the following pH values.

2.430.00372
8.652.24 x 10-9
11.741.82 x 10-12
3.680.000209
7.523.02 x 10-9

Related Problems in Chapter 9 of your textbook: Concept Check 9B problems 7 and 8