Question

The oxygen obtained from 72 kg of water is:

• A. 72 kg
• B. 46 kg
• C. 50 kg
• D. 64 kg

Answer 1

Answer: (D)

64 kg

$2H_{2}O⟶2H_2+O_2$

From above reaction, $2$ $moles$ of water produce $1$ $mole$ of $O_2$;

$2$ $mole$ of water $\to 1$ $mole$ of $O_2$

$2\times 18$ $g$ water $\to 1\times 32$ $g$ $O_2$

$36$ $g$ water $\to 32$ $g$ $O_2$

$72000$ $g$ water $\to ?\left(x\right)O_2$

$⟹x=\frac{32\times \left(72000\right)}{36}$

$⟹x=64000gram$

$=64kg$

It produces $64$ $kg$ oxygen.