Question

what is the number of moles of oxygen atom in 126 AMU of HNO3​

Answer 1

We have,

Atomic mass of HNO3 = 1 + 14 + 48 = 63 amu.

Hence, no of molecule of HNO3 =

$\frac{mass \: in \: amu}{atomic \: mass}$

= 126/63 = 2 molecules.

Now,

Number of oxygen atom in 1 molecule = 3.

Hence, there are 6 atoms in total.

Regards

Kshitij

Answer 2

Answer:6 moles

Explanation:

No.of moles in HNO3 = 126/63=2 moles (molecular mass of HNO3 = 63)

No.Of oxygen atoms in given formula are 3

So no of moles of O atom are 2 x 3 = 6 answer