Question

The stoichiometric constants for the reaction
$pCu + qHNO_3 \to rCu(NO_3)_2 + sNO + tH_2O$
$p$, $q$, $r$, $s$ and $t$ respectively are

• A. 3, 3, 3, 2, 3
• B. 3, 2, 3, 2, 4
• C. 3, 8, 3, 2, 4
• D. 2, 3, 3, 3, 2

Answer 1

Answer: (C)

Multiply Cu term with $3$ and $N$ term with $2$
$3Cu + 2HNO_{3} \to 3Cu\left(NO_{3}\right)_{2} + 2NO + H_{2}O$
Balance $H$ and $O$
$3Cu + 8HNO_{3} \to 3Cu\left(NO_{3}\right)_{2} + 2NO + 4H_{2}O$