1. 2 CH4 (g) + S8 (s) → 2CS2(l) + 4 H2S(g)
11. Methane and sulfur react to produce carbon disulfide (CS2), a liquid often used in production of cellophane.
2 CH4 (g) + S8 (s) → 2CS2(l) + 4 H2S(g)
a) Balance the equation
b) Calculate the moles of CS2 produced when 1.50 mol S8 is used.
1.50 mol S8 2mol CS2 = moles of CS2
1 mol S8
c) How many moles of H2S is produced?
1.50 mol S8 4 mol H2S = moles of H2S

2. 12. Challenge Sulfuric acid (H2SO4) is formed when sulfur dioxide (SO2) reacts with oxygen and water.
a) Write the balanced chemical equation for reaction
2 SO2 + O2 + 2 H2O → 2 H2SO4
b) How many moles of H2SO4 is produced from 12.5 moles of SO2?
12.5 moles SO2 2 mol H2SO4 = mol H2SO4
2 mol SO2
c) How many moles of O2 are needed?
12.5 moles SO2 1 mol O2 = mol O2

3. 13. Sodium is decomposed into the elements sodium and chlorine by means of electrical energy. How much chlorine gas, in grams, is obtained from the process diagrammed at right?
2 NaCl → 2 Na + Cl 2
2.50 mol ? g
2.50 mol NaCl mol Cl 2 = mol Cl2
2 mol NaCl
1.25 mol Cl g Cl 2 = g Cl2
1 mol Cl 2

4. 𝑇𝑖 𝑂 2 𝑠 +𝐶 𝑠 +2𝐶 𝑙 2 𝑔 →𝑇𝑖𝐶 𝑙 4 𝑠 +𝐶 𝑂 2 𝑔
14. Challenge Titanium is transition metal used in many alloys because it is extremely strong and lightweight. Titanium tetrachloride (TiCl4) is extracted from titanium oxide (TiO2) using chlorine and coke (carbon).
𝑇𝑖 𝑂 2 𝑠 +𝐶 𝑠 +2𝐶 𝑙 2 𝑔 →𝑇𝑖𝐶 𝑙 4 𝑠 +𝐶 𝑂 2 𝑔
a) What mass of Cl2 gas is needed to react with 1.25 mol of TiO2?
1.25 mol of TiO2 2 mol of Cl2 = mol Cl2
1 mol TiO2
2.50 mol Cl g Cl2 = g Cl2
1 mol Cl2

5. 𝑇𝑖 𝑂 2 𝑠 +𝐶 𝑠 +2𝐶 𝑙 2 𝑔 →𝑇𝑖𝐶 𝑙 4 𝑠 +𝐶 𝑂 2 𝑔
𝑇𝑖 𝑂 2 𝑠 +𝐶 𝑠 +2𝐶 𝑙 2 𝑔 →𝑇𝑖𝐶 𝑙 4 𝑠 +𝐶 𝑂 2 𝑔
b. What mass of C is needed to react with 1.25 mol of TiO2?
1.25 mol of TiO2 1 mol of C = mol C
1 mol TiO2
1.25 mol C g C = g C
1 mol C

6. 𝑇𝑖 𝑂 2 𝑠 +𝐶 𝑠 +2𝐶 𝑙 2 𝑔 →𝑇𝑖𝐶 𝑙 4 𝑠 +𝐶 𝑂 2 𝑔
𝑇𝑖 𝑂 2 𝑠 +𝐶 𝑠 +2𝐶 𝑙 2 𝑔 →𝑇𝑖𝐶 𝑙 4 𝑠 +𝐶 𝑂 2 𝑔
c. What is the mass of all of the products formed by reaction with 1.25 mol of TiO2?
1.25 mol of TiO g TiO2 = g TiO2
1 mol TiO2
99.8 g TiO g C g Cl2 = g

7. 15. One of the reactions used to inflate automobile air bags involves sodium azide (NaN3):
2 NaN3 → 2 Na + 3 N2
100.0 g ? g
100.0 g NaN3 1 mol NaN3 = mol NaN g NaN3
1.54 mol NaN3 3 mol N2 = mol N mol NaN3
2.31 mol N g N2 = g N mol N2

8. 16. Challenge In the formation of acid rain, sulfur dioxide reacts with oxygen and water to form sulfuric acid. Write the balanced chemical equation for the reaction.
2 SO2 + O2 + 2 H2O → 2 H2SO4
2.50 g ? g
2 mol SO2 = g SO = g SO2
2 mol H2SO g H2SO X g H2SO4
X = g H2SO4