Question

The number of sodium atoms in 2 moles of sodium ferrocyanide is

• A. $12 \times 10^{23}$
• B. $26 \times 10^{23}$
• C. $34 \times 10^{23}$
• D. $48 \times 10^{23}$

Answer 1

Answer: (D)

$48 \times 10^{23}$

Answer 2

Formula of sodium ferrocyanide, $Na_4[Fe(CN)_6 ]$ suggests that
it has four sodium atoms.
Number of Na atoms = no. of moles $\times$ no. of atoms per
molecule $\times$ Avogadro number
= $2 \times 4 \times 6.023 \times 10^{23}$
= $48 \times 10^{23}$