Chemistry
Calculate the relative molecular masses of :
(a) Ammonium chloroplatinate [(NH4)2PtCl6]
(b) Potassium chlorate [KClO3]
(c) CuSO4.5H2O
(d) (NH4)2Cr2O7
Mole Concept
69 Likes
Answer
(a) (NH4)2PtCl6
= (2N) + (8H) + (Pt) + (6Cl)
= (2 x 14) + (8 x 1) + 195 + (6 x 35.5)
= 28 + 8 + 195 + 213
= 444 a.m.u.
(b) KClO3
= (K) + (Cl) + (3O)
= 39 + 35.5 + (3 x 16)
= 39 + 35.5 + 48
= 122.5 a.m.u.
(c) CuSO4.5H2O
= (Cu) + (S) + (4O) + 5(2H + O)
= 63.5 + 32 + (4 x 16) + 5[(2 x 1) + 16]
= 63.5 + 32 + 64 + (5 x 18)
= 63.5 + 32 + 64 + 90
= 249.5 a.m.u.
(d) (NH4)2Cr2O7
= (2N) + (8H) + (2Cr) + (7O)
= (2 x 14) + (8 x 1) + (2 x 51.9) + (7 x 16)
= 28 + 8 + 103.8 + 112
= 251.8 ≈ 252 a.m.u.
Answered By
40 Likes
Related Questions
The gases chlorine, nitrogen, ammonia and sulphur dioxide are collected under the same conditions of temperature and pressure. The following table gives the volumes of gases collected and the number of molecules (x) in 20 litres of nitrogen. You are to complete the table giving the number of molecules in the other gases in terms of x.
Gas Volume (in litres) Number of molecules Chlorine 10 Nitrogen 20 x Ammonia 20 Sulphur dioxide 5 (i) If 150 cc of gas A contains X molecules, how many molecules of gas B will be present in 75 CC of gas B?
The gases A and B are under the same conditions of temperature and pressure.
(ii) Name the law on which the above problem is based.
Find the:
(a) number of moles in 10 g of CaCO3,
(b) weight of 0.2 mole of H2 gas,
(c) number of molecules in 3.2 g of SO2.
Which of the following would weigh most?
(a) 1 mole of H2O
(b) 1 mole of CO2
(c) 1 mole of NH3
(d) 1 mole of CO