Question

In the reaction below, hydrogen peroxide decomposes to water. MM H2O2 = 34.02 g/mol MM H2O = 18.02 g/mol MM O2 = 32 g/mol 2H2O2 → 2H2O + O2 If 14.3 moles of H2O2 is decomposed, how many grams of oxygen gas are produced? Show ALL your work to get full credit.

Answer 1

Answer: 228.8 g

Explanation:

1) Chemical equation, balanced: given

$2H_20_2---\ \textgreater \ 2H_2O + O_2$

2) mole ratios

2 mol H2O2 : 2 mol H2O :1 mol O2

3) proportion with the unknown quantity of O2:

  2 mol H2O2        14.3 mol H2O2
------------------- = -----------------------
    1mol O2                     x

4) Solve for x:

x = 14.3 mol H2O2 * 1 mol O2 / 2 mol H2O2 = 7.15 mol O2

5) Convert 7.15 mol O2 to grams

molar mass = mass in grams / number of moles

=> mass in grams = number of moles * molar mass

molar mass of O2 = 2 * 16.00 g/mol = 32.00 g/mol

mass in grams O2 = 7.15 moles * 32.00 g / mol = 228.8 g

Answer: 228.8 g