An element X has the following isotopic composition,
200X : 90%, 199X : 8.0%, 202X : 2.0%
The weighted average atomic mass of the naturally occurring element X is closest to:
1. | 205 u | 2. | 220 u |
3. | 196 u | 4. | 200 u |
0.24g of a volatile gas, upon vaporisation, gives 45 mL vapour at NTP. What will be the vapour density of the substance?
(Density of H2 = 0.089)
1. 95.93
2. 59.93
3. 95.39
4. 5.993
The hydrated salt, Na2SO4.nH2O, undergoes a 55% loss in mass on heating and becomes anhydrous. The value of n will be:
1. | 5 | 2. | 3 |
3. | 7 | 4. | 10 |
12 g of Mg (atomic mass = 24) will react completely with an acid to yield:
1. One mole of H2
2. A half mole of H2
3. One mole of O2
4. None of the above
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
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 sulfate 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.