Question

1.Calculate the number of molecules in 7.0g of nitrogen.​

Answer 1

$\huge{\mathcal{\blue{\underline{Answer}}}}$

Molar mass of nutrogen = 14u

Given mass = 7gram

$moles = \frac{given \: mass}{molar \: mass} \\ moles = \frac{7g}{14u} = 0.5$

$1mol = 6.022 \times 10 {}^{23} molecules$

Hence 0.5mol contains :

$= 0.5 \times 6.022 \times 10 {}^{23} \\ = 3.011 \times 10 {}^{23} molecules$