Question

How many millimoles of NaOH contain 5.63 x 10^22 formula units of NaOH

Answer 1

1 mole of NaOH would have $6.02 ×10^{23}$ (avogadro's constant)

Molar mass of NaOH = 40

Hence

$5.63×10^{22}$  formula units of NaOH will have mass:

$(\frac{40}{6.02×10^{23}} ) 5.63 ×10^{22} = 3.74g$

In millimoles = $\frac{3.74}{1000}= 0.00374 millimoles$