Some Basic Concepts of Chemistry - Result Question 13 — JEE PYQ Chapterwise

Answer:

Correct Answer: 17. (b)

Solution:

17. $\dfrac{n_{\mathrm{O}2}}{n{\mathrm{N}2}}=\dfrac{\dfrac{\left(m{\mathrm{O}2}\right)}{\left(M{\mathrm{O}2}\right)}}{\dfrac{\left(m{\mathrm{N}2}\right)}{\left(M{\mathrm{N}_2}\right)}}$

where, $m_{\mathrm{O}_2}=$ given mass of $\mathrm{O}2, m{\mathrm{N}_2}=$ given mass of $\mathrm{N}_2$,

$M_{\mathrm{O}_2}=$ molecular mass of $\mathrm{O}2, M{\mathrm{N}_2}=$ molecular mass of $\mathrm{N}_2$,

$n_{\mathrm{O}_2}=$ number of moles of $\mathrm{O}2, n{\mathrm{N}_2}=$ number of moles of $\mathrm{N}_2$

$=\left[\frac{m_{\mathrm{O}2}}{m{\mathrm{N}_2}}\right] \frac{28}{32}=\frac{1}{4} \times \frac{28}{32}=\frac{7}{32}$