Chapter 13.2, Problem 8RQ

Interpretation Introduction

Interpretation:

The volume of oxygen gas needs to be determined.

Concept Introduction:

Water decomposes by electric current to give hydrogen and oxygen.

The balanced chemical equation is-

  $2H_{2}O(l)\to 2H_2(g)+O_2(g)$

Answer to Problem 8RQ

The volume of oxygen gas is 0.679 litre.

Explanation of Solution

Data given: Mass of water = 1.0 gm

Pressure = 1.00 atm

Temperature = 25 °C = 298 K The balanced chemical equation is-

  $2H_{2}O(l)=2H_2(g)+O_2(g)$

Number of moles of water = 1.0/18 = 0.0556

So, number of moles of oxygen = 0.0278

The ideal gas equation is- $PV=nRT$

  $\begin{array}{l}V=\frac{nRT}{P}=\frac{0.0278mol\times 0.082Latm/molK\times 298K}{1.00atm}\\ =0.679L\end{array}$