Q42 / 180 · AIIMS 2015 · Chemistry

For the reaction of one mole of zinc dust with one mole of sulphuric acid in a bomb calorimeter, $\Delta U$ and $w$ correspond to

Correct answer
A
$\Delta U < 0, w=0$
B
$\Delta U < 0, w < 0$
C
$\Delta U>0, w=0$
D
$\Delta U>0, w>0$

Solution

Bomb calorimeter commonly used to find the heat of combustion of organic substances, consists of a sealed combustion chamber, called a bomb. The reaction in a bomb calorimeter proceeds at constant volume so, $w=0$ and $\Delta U=q$. Hence, $\Delta U < 0, w=0$.

Hence, the correct answer is option: 'A'.

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