The conversion of oxygen to ozone occurs to the extent of 15% only. The mass of ozone that can be prepared from 67.2 L oxygen at 1 atm and 273 K will be:
1. 14.4 gm
2. 96 gm
3. 640 gm
4. 64 gm
A silver coin weighing 11.34 g was dissolved in nitric acid. When sodium chloride was added to the solution all the silver (present as ) was precipitated as silver chloride. The weight of the precipitated silver chloride was 14.35 g. Calculate the percentage of silver in the coin.
1. 4.8%
2. 95.2%
3. 90%
4. 80%
Rearrange the following (I to IV) in the order of increasing masses:
(I) 0.5 mole of O3
(II) 0.5 gm atom of oxygen
(III) 3.0111023 molecules of O2
(IV) 5.6 liter of CO2 at STP
1. | II<IV<III<I | 2. | II<I<IV<III |
3. | IV<II<III<I | 4. | I<II<III<IV |
It is known that atom contains protons, neutrons and electrons. If the mass of neutron is assumed to half of its original value whereas that of proton is assumed to be twice of its original value then the atomic mass of will be:
1. same
2. 14.28% less
3. 14.28% more
4. 28.56% less
Nitric acid can be produced in three steps process
(I)
(II)
(III)
percent yield Ist, IInd and IIIrd are respectively 50%, 60% and 80% respectively then what volume of at 1 atm and 0C required to produces 1575 g of
1. 156.25
2. 350 L
3. 3500 L
4. None of these
Density of dry air containing only and is 1.15 g/L at 740 mm and 300 K. What is % composition of by weight in the air?
1. 78%
2. 75.5%
3. 70.02%
4. 72.75%
In preparation of iron from haematite by the reaction with carbon
How much 80% pure iron could be produced from 120 kg of 90% pure ?
1. 94.5 kg
2. 60.48 kg
3. 116.66 kg
4. 120 kg
A gaseous mixture of and gas contains 66 mass % of . The vapour density of the mixture is:
1. 6.1
2. 5.4
3. 2.7
4. 10.8
What volume of 75% alcohol by weight (d=0.80g/) must be used to prepare 150 of 30% alcohol by weight (d=0.90 g/)?
1. 67.5 mL
2. 56.25 mL
3. 44.44 mL
4. None of these
Average atomic mass of magnesium is 24.31 a.m.u. This magnesium is compound of 79 mole% of and remaining 21 mole % of and . Calculate mole% of .
1. 10
2. 11
3. 15
4. 16