Question

Which of the following contains maximum number of atoms?
A. 18g of water
B. 16g of o2
C. 4.4g of co2
D. 16g of ch4

Answer 1

Explanation:

Given -

1. 18g of H2O
2. 16g of O2
3. 4.4g of CO2
4. 16g of CH4

To Find -

• Which of the following contains maximum number of atoms?

As we know that :-

• mass = n(mole) × GAM/GMM
• No. of molecules = n × Na

Now,

We have to check all compound to say which contains maximum number of atoms.

Option 1)

18g of H2O

Solution :-

GMM of H2O = 1×2 + 16 = 18 g/mol

mole of H2O = 18/18 = 1 mol

Now,

No. of molecules = 1 × 6.022 × 10²³

➳ 6.022 × 10²³ atoms are present in 18 g of H2O

Option 2)

16g of O2

Solution :-

GAM of O2 = 16×2 = 32 g/mol

mole of O2 = 16/32 = 1/2 mol

Now,

no. of molecules = 1/2 × 6.022 × 10²³

➳ 3.011 × 10²³ atoms are present in 16g of O2

Option 3)

4.4g of CO2

Solution :-

GMM of CO2 = 12 + 16×2 = 12 + 32 = 44 g/mol

mole of CO2 = 4.4/44 = 1/10 mol

Now,

no. of molecules = 1/10 × 6.022 × 10²³

➳ 6.022 × 10²² atoms are present in 4.4 g of CO2

Option 4)

16g of CH4

Solution :-

GMM of CH4 = 12 + 1×4 = 12 + 4 = 16 g/mol

mole of CH4 = 16/16 = 1 mol

Now,

no. of molecules = 1 × 6.022 × 10²³

➳ 6.022 × 10²³ atoms are present in 16g of CH4

Hence,

Both (18g of H2O and 16g of CH4) contains same no. of atoms.

Therefore,

Option I and Option IV (Both) are correct.

(More than one correct question)