MCQ
$10\,g$ of $CaCO_3$ contains
  • A
    $10\,moles$ of $CaCO_3$
  • $0.1\,g$ atom of $Ca$
  • C
    $6\times 10^{23}$ atoms of $Ca$
  • D
    $0.1$ of equivalent of $Ca$

Answer

Correct option: B.
$0.1\,g$ atom of $Ca$
b
Mwt of $\mathrm{CaCO}_{3}=40+12+48=100$

$ \text { Moles of } \mathrm{CaCO}_{3} \text { in } 10 \,\mathrm{g} =\frac{10}{100} $

$=0.1\, \mathrm{mol}=0.1 \,\mathrm{g} \,\text { atom }$

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