Examine the samples given:

a. 20 g of He

b. 44.8 L of NH₃ at STP

c. 67.2 L of N₂ at STP

d. 1 mol of H₂SO₄

e. 180 g of water What will be the ascending order of the total number of atoms in each sample?

Calculation of number of atoms in each:

a. Number of molecules = 3.011 × 10²⁴ (calculated)

In He, there is only one atom

Thus, total number of atoms of He = 1 × Number of molecules

= 3.011 × 10²⁴

b. Number of molecules = 1.204 × 10²⁴ (calculated)

In NH₃, there are four atoms

Thus, total number of atoms of NH₃ = 4 × Number of molecules

= 4 × 1.204 × 10²⁴

= 4.8 × 10²⁴

c. Number of molecules = 1.806 × 10²⁴ (calculated)

In N₂, there are two atoms

Thus, total number of atoms of N₂ = 2 × Number of molecules

= 2 × 1.806 × 10²⁴

= 3.6 × 10²⁴

d. Number of molecules = 6.022 × 10²³ (calculated)

In H₂SO₄, there are seven atoms

Thus, total number of atoms of H₂SO₄ = 7 × No. of molecules

= 7 × 6.022 × 10²³

= 4.21 × 10²⁴

e. Number of molecules = 6.022 × 10²⁴ (calculated)

In H₂O, there are three atoms

Thus, total number of atoms of H₂O = 3 × Number of molecules

= 3 × 6.022 × 10²⁴

= 1.8 × 10²⁵

The arrangement of the samples in increasing order of the number of atoms in each is:

20 g of He < 67.2 L of N₂ at STP < 1 mol of H₂SO₄ < 44.8 L of NH₃ at STP < < 180 g of water