Question

The ratio of masses of oxygen and nitrogen in a
particular gaseous mixture is 1 : 4. The ratio of
number of their molecule is

Answer 1

Answer:

Mass Ratio of O2:N2 = 1 : 4. Therefore mole ratio= (1/32): (4/28) = 28 : 112 =7 : 32.

Answer 2

Answer :

• The ratio of number of their molecules = 7 : 32.

Step-by-step explanation :

Given that,

• The ratio of masses of oxygen & nitrogen = 1 : 4.

Also,

• Molar mass of $\rm{O_2}$ = 32 g/mol.
• Molar mass of $\rm{N_2}$ = 28 g/mol.

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Given that, ratio of their masses = 1 : 4

Then, Suppose,

† Mass of oxygen in mixture = x grams.

† Mass of nitrogen in mixture = 4x grams.

Now, we know,

No. of molecules = No. of moles × Avogadro's number.

Therefore,

$\rm{No.\:of\:molecules\:of\:oxygen=\dfrac{x}{32}\times{}N_0}$

$\rm{No.\:of\:molecules\:of\:nitrogen=\dfrac{4x}{28}\times{}N_0}$

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Then, ratio of number of molecules =

$\implies\rm{\dfrac{x\times{}N_0}{32}\times{}\dfrac{28}{4x\times{}N_0}}$

$\implies\rm{\dfrac{28}{32\times{}4}=\dfrac{7}{32}=}\:\bold{7:32.}$