Question

Determine from the balanced chemical reaction if the derived mole ratio is correct or incorrect.

Answer 1

Answer:

Balanced reaction: $4Zn+10HNO_{3}\rightarrow 4Zn(NO_{3})_{2}+N_{2}O+5H_{2}O$

The mole ratio (4 moles Zn/5 moles $H_{2}O$) is correct.

Explanation:

Oxidation: $Zn\rightarrow Zn(NO_{3})_{2}$

Balance N and O: $Zn+2NO_{3}^{-}\rightarrow Zn(NO_{3})_{2}$

Balance charge: $Zn+2NO_{3}^{-}-2e^{-}\rightarrow Zn(NO_{3})_{2}$    ................(1)

Reduction: $HNO_{3}\rightarrow N_{2}O$

Balance N: $2HNO_{3}\rightarrow N_{2}O$

Balance H and O: $2HNO_{3}+8H^{+}\rightarrow N_{2}O+5H_{2}O$

Balance charge: $2HNO_{3}+8H^{+}+8e^{-}\rightarrow N_{2}O+5H_{2}O$  ............. (2)

[$4\times$Equation-(1)] + [Equation-(2)]:

$4Zn+8NO_{3}^{-}+2HNO_{3}+8H^{+}\rightarrow 4Zn(NO_{3})_{2}+N_{2}O+5H_{2}O$

$\Rightarrow 4Zn+10HNO_{3}\rightarrow 4Zn(NO_{3})_{2}+N_{2}O+5H_{2}O$

So, balanced reaction: $4Zn+10HNO_{3}\rightarrow 4Zn(NO_{3})_{2}+N_{2}O+5H_{2}O$

Hence the mole ratio (4 moles Zn/5 moles $H_{2}O$) is correct.