Question

How many liters of hydrogen gas are needed to produce 120.0 grams of water at 25.0°C and 1.00 atm pressure according to the chemical equation shown below   

2 H 2 (s)+O 2 (g) 2 H 2 O(l)

Answer 1

2 H2 (g) +O2(g) 2 H2O (l)

Molar mass of H2O = 18.01528 g/mol

given mass of H2O =120.0 gram

moles of H2O = [120 .0 g]/[18.01528 g/mol] = 6.66 moles of H2O

According to balanced equation mole ratio of H2:H2O is 1:1

so 6.66 moles of H2O will be produed by 6.6 moles of H2

PV = nRT

P= 1 atm

T= 25 degree celsius= 25+273.15 K =298.15 K

R =0.0821 atm.L.mol-1K-1

n =6.66 mol

V = nRT/P

= [6.66 mol*0.0821 atm.L.mol-1K-1 *298.15 K]/[1 atm] = 163.02 liter

Volume =163.02 liter