Question

Hydrogen peroxide (H2O2) will decompose into water (H2O)and oxygen gas (O2). What mass of hydrogen peroxide is required to produce 72.5 g of water? The molar mass of hydrogen peroxide is 34.0147 g/mol, and the molar mass of water is 18.0153 g/mol.
options:
a) 38.4g
b) 0.112g
c) 2.73 × 102 g
d) 1.37 × 102 g

Answer 1

Answer:

Option d ) 1.37 × 10² g

is the right answer.

Explanation:

given:

$2H_2O_2 -->2H_2O \ + O_2$

to find :

mass of hydrogen peroxide required to produce 72.5 g of water (i.e.,)  4.0244 moles of water.

From the equation ,it is clear to  produce 2 moles of water we require 2 moles of hydrogen peroxide .

so, to produce 4.0244 moles of water , we require 4.0244 moles of hydrogen peroxide .

we know that,

No. of moles = given mass / molar mass

by using this formula ,

mass of $H_2O_2$ required to produce 72.5 g of water = 4.0244 * 34.0147

                                                                                    = 136.88

                                                                                    ≅ 1.37 × 10² grams