Question

The two balanced equations (1) and (2) are for reactions in which gaseous carbon dioxide is produced from the combustion of (1) solid carbon and (2) gaseous carbon monoxide.

1. C(s) + O2(g) CO2(g) + 94.0 kcal
2. CO(g) + ½ O2(g) CO2(g) + 67.6 kcal
When 112 grams of carbon monoxide are consumed according to equation 2, which of the following occurs? (atomic weights: C = 12.0 g/mol, O = 16.0 g/mol)
1.0 mole of carbon dioxide is produced.
67.6 kcal of heat are generated.
2.0 moles of oxygen are consumed.
0.25 mole of carbon dioxide is produced.
0.50 mole of oxygen is consumed.

Answer 1

2.0 mol of oxygen are consumed.

Step-by-step explanation:

You know that you will need a balanced equation with masses, moles, and molar masses, so gather all the information in one place.

M_r: 28.0 44.0

CO + ½O₂ ⟶ CO₂ + 67.6 kcal

m/g: 112

Step 1. Convert grams of CO to moles of CO

1 mol CO = 28.0 g CO

Moles of CO = 112 × 1/28.0

Step 2. Convert moles of CO to moles of CO₂.

The molar ratio is 1 mol CO₂ to 1 mol CO

Moles of CO₂ = 4.000 × 1/1

Moles of CO₂ = 4.00 mol CO₂

Option A is wrong.

Step 3. Calculate the amount of heat generated.

q = ΔH

The conversion factor is 67.6 kcal/1 mol CO₂

q = 4.00 × 67.6

q = 270 kJ

Option B is wrong, because it gives the heat generated by 1 mol of CO.

Step 4. Calculate the moles of O₂ consumed

Moles of O₂ = 2.00 mol O₂

Option C is correct.

Step 5. Calculate the moles of CO₂ formed

Already done in Step 2.

Moles of CO₂ = 4.00 mol CO₂

Option D is wrong.

Step 6. Calculate the moles of O₂ produced

Already done in Step 4.

Moles of O₂ = 2.00 mol O₂

Option E is wrong.