To account for the atomic mass of nitrogen as 14.0067,\(\mu\) what should be the ratio of and atoms \({ 15 }_{ N }\)\({ 14 }_{ N }\) in natural nitrogen? (atomic mass of \({ 14 }_{ N }\) = 14.00307 \(\mu\) and \({ 15 }_{ N }\) = 15.001\(\mu\))

3

(a)

A compound contains 4.07% hydrogen, 24.27% carbon and 71.65% chlorine. Its molar mass is 98.96 g. What are its empirical and molecular formulas?

3

(a)

Convert the following into metre
(i) 40 Em (thickness of Milky way galaxy)
(ii) 1.4 Gm (diameter of Sun)
(iii) 41 Pm (distance of nearest star)

3

(a)

Calculate the percentage by mass of chromium in the following oxide.
(a) 'CrO'
(b) 'Cr₂O₃'
(c) 'CrO₃'

3

(a)

Express the following up to four significant figures. '6.5089'

3

(a)

Express the following up to four significant figures. '8.721 x 10⁴'

3

(a)

Express the following up to four significant figures. '2000'

3

(a)

Calculate the number of moles in each of the following.
44.8 litres of sulphur dioxide at N.T.P.

3

(a)

Calculate the number of moles in each of the following.
8g of calcium

3

(a)

Calculate:
(a) Mass of 2.5 gram atoms of magnesium,
(b) Gram atom in 1.4 grams of nitrogen (Atomic mass Mg = 24, N = 14)

3

(a)