Question

When 1 g of anhydrous oxalic acid is burnt at ${25}^{0}C$, the amount of heat liberated is $2.835kJ$. $△H$ combustion is: (oxalic acid: $C_2{H}_2{O}_4$):

• A. $-255.15kJ$
• B. $-445.65kJ$
• C. $-295.24kJ$
• D. $-155.16kJ$

Answer 1

The correct option is A $-255.15kJ$

Oxalic acid $C_2{H}_2{O}_4$

Molar mass $=90$

Mass $=\frac{1}{90}molar$

$(\Delta H_{comb}{)}_{C_2{H}_2{O}_4}=-\frac{\text{Heat Liberated}}{\text{moles}}$

$=-\frac{2.835kJ}{1/90}$

$=-255.15kJ$