MCQ
$19.7\, kg$ of gold was recovered from a smuggler. How many atoms of gold were recovered ($Au =197$)
- A$100$
- B$6.02 \times {10^{23}}$
- C$6.02 \times {10^{24}}$
- ✓$6.02 \times {10^{25}}$
✓
Answer
Correct option: D.
$6.02 \times {10^{25}}$
d
(d) Amount of gold $ = 19.7\,kg$ $ = $$19.7$$ \times 1000\,gm$ = $19700\,gm$
(d) Amount of gold $ = 19.7\,kg$ $ = $$19.7$$ \times 1000\,gm$ = $19700\,gm$
No. of moles $ = \frac{{19700}}{{197}} = 100$
$\therefore $ No. of atoms $ = 100 \times$ $6.023 \times {10^{23}}$
$ = 6.023 \times {10^{25}}$ atoms.
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