Question

The work done in an open vessel at 300 K, when 112 g iron reacts with dil HCl is :

• A. 1200 cal
• B. 600 cal
• C. 300 cal
• D. 200 cal

Answer 1

The correct option is A 1200 cal

$Fe+2HCl\to FeC{l}_2+H_{2}1mol1mol\frac{112}{56}=2mol2molNow,V_2=V_{H_2}and{V}_1=0$
(For solid + liquid state)
Work done $=p(v_2-v_1)=p(H_2-0)=p{V}_{H_2}=n_{H_2}RT=2\times 2\times 300=1200cal$