The molality of a 15% (w/vol.) solution of H2SO4 of density 1.1g/cm3 is-
1. 1.2
2. 1.4
3. 1.8
4. 1.6
H3PO4 is a tribasic acid and one of its salts is NaH2PO4. What volume of 1 M NaOH should be added to 12g NaH2PO4 (Molar mass 120) to exactly convert it into Na3PO4?
1. 100 mL
2. 300mL
3. 200mL
4. 80mL
Which mode of expressing concentration is independent of temperature?
1. Molality
2. Percent by mass
3. Mole fraction
4. All of the above
The product of atomic mass and specific heat of metal is approximately 6.4. This was given by:
1. Dalton's law
2. Avogadro's law
3. Newton's law
4. Dulong Petit's law
A metal M forms a compound M2HPO4. The formula of the metal sulphate is:
1. M2SO4
2. MSO4
3. M(SO4
4. M2(SO4)3
A partially dried clay mineral contains 8% water. The original sample contained 12% water and 45% silica. The percentage of silica in the partially dried sample is nearly:
1. | 50% | 2. | 49% |
3. | 55% | 4. | 47% |
One litre N2, 7/8 litre O2 and 1 litre CO are taken in a mixture under indentical conditions of P and T. The amount of gases present in mixture is given by:
1.
2.
3.
4.
Equal volumes of 0.1 M AgNO3 and 0.2 M NaCl are mixed. The concentration of N ions in the mixture will be:
1. | 0.1M | 2. | 0.05M |
3. | 0.2M | 4. | 0.15M |
A solution contains Na2CO3 and NaHCO3. 10 mL of the solution required 2.5 mL of 0.1 M H2SO4 for neutralisation using phenolphthalein as indicator. Methyl orange is then added when a further 2.5 mL of 0.2 M H2SO4 was required. The amount of Na2CO3 and NaHCO3 in 1 litre of the solution is:
1. 5.3g and 4.2g
2. 3.3g and 6.2g
3. 4.2g and 5.3g
4. 6.2g and 3.3g
A sample of pure Cu (3.18g ) heated in a stream of oxygen for some time gains in mass with the formation of black oxide of copper (CuO). The final mass is 3.92 g. The percent of copper remains unoxidised is-
1.6.5
2.6.9
3. 7.6
4. 7.9