Question

Number of atoms present in 280u of nitrogen ( N2) is
•10
•20
•30
•40​

Answer 1

The mass of one atom of nitrogen is 14 u

We have to find out the number of nitrogen atoms in 280u

Let x be the number of nitrogen atoms having a mass of 280 u

mass of 1 nitrogen atom = 14 u

mass of x nitrogen atom = 280 u

mass of x nitrogen atom= 280/14

                                         = 20

So, 20 nitrogen atoms will have a mass of 280u.

The correct answer will be option b.

Answer 2

Answer:

According to question we have to find out the number of nitrogen atoms in 280u .

Let x be the number of nitrogen atoms having a mass of 280 u

As we know , The mass of one atom of nitrogen = 14 u

mass of x nitrogen atom = 280 u

mass of x nitrogen atom= 280/14

 = 20

So, the number of atoms present in 280 μ is 20.

hence , option' b ' is correct .