Question

How many atoms are present in $1kg$ of silver?

[Atomic mass of silver $=108$]

• A. $2.03\times {10}^{23}atoms$
• B. $5.57\times {10}^{24}atoms$
• C. $4.27\times {10}^{-23}atoms$
• D. $6.23\times {10}^{23}atoms$

Answer 1

The correct option is B $5.57\times {10}^{24}atoms$

No. of moles $=\frac{\text{Mass of substance(g)}}{\text{Molar mass}}$

$=\frac{1000g}{108g}$

$=9.259$

No. of atoms $=9.259\times 6.022\times {10}^{23}atoms$.

$=5.57\times {10}^{24}atoms$.

Hence, option B is correct.