Question

what is the weight of 1.5 × 10^24 atoms of N2?​

Answer 1

Answer:

A] 2g atoms of nitrogen means 2×14=28g.

B] 1 mole of silver = 107.8g.

C] 22.4 litres of oxygen = 32g.

D] 6.02×10

23

atoms = 1 mole = 12 g of carbon.

So, option (D) has the least weight.

Answer 2

Given :

Number of atoms = 1.5 × 10²⁴

To Find :

Weight of N₂

Solution :

❒ Since N₂ is a diatomic molecule, we can say that one molecule of N₂ contains two atoms of nitrogen.

Number of molecules of N₂ :

$\sf:\implies\:N=\dfrac{Number\:of\:atoms}{2}$

$\sf:\implies\:N=\dfrac{1.5\times 10^{24}}{2}$

$\sf:\implies\:N=0.75\times10^{24}\:molecules$

We know that, 1 mole of substance contains 6.022 × 10²³ molecules.

$\sf:\implies\:Moles=\dfrac{N}{6.022\times10^{23}}$

$\sf:\implies\:n=\dfrac{0.75\times 10^{24}}{6.022\times 10^{23}}$

$\sf:\implies\:n=0.124\times 10$

$\bf:\implies\:n=1.24\:moles$

❒ Molar mass of N₂ = 28 g/mol

It means weight 1 mole of N₂ = 28

∴ Weight of 1.24 moles of N₂ :-

➠ W = n × 28

➠ W = 1.24 × 28

➠ W = 34.72 g