The following data are obtained when dinitrogen and dioxygen react together to form different compounds:
`{:(," Mass of dinitrogen ","Mass of dioxygen"),( (i), 14 g ,16 g),( (ii), 14 g, 32 g ),((iii), 28 g ,32 g ),((iv) ,28 g, 80 g ) :}`
(a) Which law of chemical combination is obeyed by the above experimental data? Give its statement.
(b) Fill in the blanks in the following conversions:
(i) 1 km = ...................... mm = ...................... pm
(ii) 1 mg = ...................... kg = ...................... ng
(iii) 1 mL = ...................... L = ...................... `dm^(3)`

Explanation

Fixing the mass of dinitrogen as `28 g`, masses of dioxygen combined will be `32, 64, 32`, and `80 g` in the given four oxides. These are in the ratio `1:2:1:5` which is a simple whole number ratio. Hence, the given data obey the law of multiple proportions.
b. i. `1 km=1 kmxx(1000 m)/(1 km)xx(100 cm)/(1 m)xx(10 mm)/(1 cm)=10^(6) mm`
`1 km=1 kmxx(1000 m)/(1 km)xx(1 "pm")/(10^(-12)m)=10^(15) "pm"`
ii. `1 mg=1 mgxx(1g)/(1000mg)xx(1 kg)/(1000 g)=10^(-6) kg`
`1 mg=1 mgxx(1g)/(1000 mg)xx(1 ng)/(10^(-9)g)=10^(6) ng`
iii. `1 mL=1 mLxx(1L)/(1000mL)=10^(-3) L`
`1 mL=1 cm^(3)`
`=1 cm^(3)xx(1dmxx1dmxx1dm)/(10 cmxx10 cmxx10 cm)=10^(-3) dm^(3)`