Question

find the number of atoms present in 126gram of HNO3 ​

Answer 1

Answer:

Given:

126 g of HNO3 has been provided.

To find:

Number of atoms.

Calculation:

Molar mass of HNO3 = 63 g/mol.

∴ No. of moles of HNO3 present

= 126/63

= 2 moles.

Now, number of atoms in 1 molecule of HNO3 = 5 atoms.

∴ total number of atoms in 1 mole

= 5 × (Avagadro No.)

∴ Total atoms in 2 moles

= 2 × { 5 × ( Avagadro No.)}

= 10 × (Avagadro No.)

= 10 × 6.0223 × 10^23

= 6.0223 × 10^24 atoms.

Answer 2

AnSweR:

$\longrightarrow\:$ 6.022×10^24 atoms

CalCuLaTion:

• Given Mass: 126 g

• Molecular Mass of HNO3 : 1+7+16×3

= 63 g/mol

• First we calculate no. of moles

no. of moles = given mass/molecular mass

= 126/63 = 2 moles

• Now, No. of atoms in HNO3 = 5

Number of atoms present =

=5×2× Avogadro's Number

= 10× 6.022×100^23 atoms

= 6.022×10^24