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The following data are obtained when dinitrogen and dioxygen react together to form different compounds - CBSE (Science) Class 11 - Chemistry

ConceptLaws of Chemical Combination Law of Multiple Proportions

Question

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 = ...................... dm3

Solution

(a) If we fix the mass of dinitrogen at 28 g, then the masses of dioxygen that will combine with the fixed mass of dinitrogen are 32 g, 64 g, 32 g, and 80 g.

The masses of dioxygen bear a whole number ratio of 1:2:2:5. Hence, the given experimental data obeys the law of multiple proportions. The law states that if two elements combine to form more than one compound, then the masses of one element that combines with the fixed mass of another element are in the ratio of small whole numbers.

(b)

(i) 1 km = 1 km xx (1000m)/(1km)xx(100cm)/(1m)xx(10mm)/(1cm)

∴1 km = 106 mm

1 km = 1 km xx(1000m)/(1km)xx(1"pm")/(10^-12m)

∴1 km = 1015 pm

Hence, 1 km = 106 mm = 1015 pm

(ii) 1 mg = 1 mg xx(1g)/(1000mg)xx(1kg)/(1000g)

⇒ 1 mg = 10–6 kg

1 mg = 1 mg xx(1g)/(1000mg)xx(1ng)/(10^-9g)

⇒ 1 mg = 106 ng

∴ 1 mg = 10–6 kg = 106 ng

(iii) 1 mL = 1  mLxx(1  L)/(1000  mL)

⇒ 1 mL = 10–3 L

1 mL = 1 cm3 = 1 cm3(1dmxx1dmxx1dm)/(10cmxx10cmxx10cm)

⇒ 1 mL = 10–3 dm3

∴ 1 mL = 10–3 L = 10–3 dm3

Is there an error in this question or solution?
Solution The following data are obtained when dinitrogen and dioxygen react together to form different compounds Concept: Laws of Chemical Combination - Law of Multiple Proportions.
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