The sulphate of a metal M contains 9.87% of M. The sulphate is isomorphous with ZnSO4.7H2O. The atomic weight of M is
40.3
36.3
24.3
11.3
10dm3 of N2 gas and 10 dm3 of gas X at the same temperature contain the same number of molecules. The gas X is
CO
CO2
H2
NO
The number of water molecules present in a drop of water (volume 0.0018 mL) at room temperature is :
6.023 × 1019
1.084 × 1018
4.80 × 1017
6.023 × 1023
Assuming that the density of water to be 1g/cm3, calculate the volume occupied by one molecule of water
2.989 × 10-23 cm3
6.023 × 1023 cm3
22400 mL
18 cm3
One mole of calcium phosphide on reaction with excess of water gives
One mole of phosphine
Two moles of phosphoric acid
Two moles of phosphine
One mole of phosphorous pentoxide
A metal oxide contains 53% metal and carbon dioxide contains 27% carbon. Assuming the law of reciprocal proportions, the percentage of metal in the metal carbide is
75
25
37
66
If 1 mL of water contains 20 drops, what is the number of water molecules in the one drop of water ? (A = Avogadro number)
0.5/18 A
0.05 A
0.05/18 A
0.5 A
If 0.5 moles of BaCl2 are mixed with 0.2 moles of Na3PO4, the maximum number of moles of Ba3(PO4)2 that can be formed is:
0.7
0.5
0.30
0.10
30 g of magnesium and 30 g of oxygen are reacted, then the residual mixture contains
60 g of magnesium oxide only
40 g of magnesium oxide and 20 g of oxygen
45 g of oxygen and 15 g of magnesium oxide
50 g of magnesium oxide and 10 g of oxygen
What is the percentage of water of crystallisation in a sample of blue vitriol ?
34.07%
35.07%
36.07%
37.07%
