Answer to Question #167377 in General Chemistry for Tjamilon

Question

What volume of H2 gas at STP would be produced during the passage of 30,000 Coul in the electrolysis of H2 O? 

 

Answer 1

Ans:-

A coulomb is $1.036 \times10^{-5}$ mole of elementary electric charges (electrons, protons, or singly charged ions).

$1$ mole of any ideal gas is $22.4 liters$ at STP. Hydrogen gas is $H_2$ and very close to an ideal gas at STP.

$\Rightarrow$ $3.0000\times10^4$ $Coulomb$ x $1.036 \times10^{-5}$ Mole/Coulomb = $3.108 \times10^{-1}$ Mole (of H)

$\Rightarrow$ $0.3108$ Mole (H) $\times$ $\dfrac{1\times{H_2} }{2\times{H}}$ $=$ $0.1554 mole (H_2)$

$\Rightarrow$ $22.4\dfrac{liters}{mole}\times0.1554 mole$ $= 3.481 liters$ . ($H_2$ at STP)