Question

the no of molecules present in 2.8g of nitrogen​

Answer 1

Answer:

1.2 ×10∧23 molecules

Explanation:

Nitrogen is an element in the periodic table

The relative molecular mass of nitrogen is 14

To get the number of molecules present we 1st find the  moles present

Moles = mass/relative molecular mass

2.8 ÷ 14 = 0.2 moles

One mole of any substance is always equal to the avogadro's number of particles 6.0 × 10∧23

Therefore

0.2 moles × 6.0 × 10∧23

= 1.2 × 10∧23 molecules

Answer 2

Answer:

The number of molecules present in 2.8 g of nitrogen is $\bold{6.02 \times 10^{22}}$

Explanation:

To find the number of moles present in the 2.8 g of nitrogen.

That is given the mass of nitrogen is 2.8 g

Step 1  

To determine the number of moles of nitrogen.

We know that,

Number of moles in nitrogen is given by,

Given mass/molar mass of the nitrogen

From the given statement given mass is 2.8g

The molar mass of the nitrogen is 28g/mol

So, by substituting the values we have

Number of moles $= \frac{2.8}{28}$

=0.1 mole

Step 2

To find the number of molecules present

$=0.1 \times 6.023 \times 10^{23}$

Where 6.023 x 1023 is an Avogadro number

$=6.02 \times 10^{22}$