Percentage of C, H & N of a compound is given as follows:
C=40%, H=13.33%, N=46.67%
The empirical formula of the compound will be:

1. $C{H}_{2}N$

2. $C_2{H}_{4}N$

3. $C{H}_{4}N$

4. $C{H}_{3}N$

 The empirical formula of an oxide of iron, which has 69.9% iron and 30.1% oxygen by mass is -

1. FeO

2. Fe₂O₃

3. Fe₃O₄

4. Fe₃O₂

 If 2.74 g of the metal oxide contains 1.53 g of metal, then the empirical formula of vanadium oxide is:

(Atomic Mass of V = 52)

1. ${\mathrm{V}}_2{\mathrm{O}}_3$

2. $\mathrm{VO}$

3. ${\mathrm{V}}_2{\mathrm{O}}_5$

4. ${\mathrm{V}}_2{\mathrm{O}}_7$