Some Basic Concepts of Chemistry

Concentrated nitric acid is labelled as 75% by mass. The volume in mL of the solution which contains 30 g of nitric acid is . Given : Density of nitric acid solution is 1.25 g/mL.

1. 32
2. 40
3. 55
4. 45

Consider the following reaction occurring in the blast furnace: Fe3O4(s) + 4CO(g) 3Fe(l) + 4CO2(g) 'x' kg of iron is produced when 2.32 103 kg Fe3O4 and 2.8 102 kg CO are brought together in the furnace. The value of 'x' is . (nearest integer) Given: molar mass of Fe3O4 = 232 g mol-1 molar mass of CO = 28 g mol-1 molar mass of Fe = 56 g mol-1

Xg of benzoic acid on reaction with aq NaHCO3 released CO2 that occupied 11.2 L volume at STP. X is g.

The elemental composition of a compound is 54.2\% C, 9.2\% H and 36.6\% O. If the molar mass of the compound is 132 g mol-1, the molecular formula of the compound is : [Given : The relative atomic mass of C:H:O=12:1:16]

1. C4H8O2
2. C6H12O6
3. C4H9O3
4. C6H12O3

What amount of bromine will be required to convert 2 g of phenol into 2,4,6-tribromophenol? (Given molar mass in g mol-1 of C, H, O, Br are 12, 1, 16, 80 respectively )

1. 6.0 g
2. 10.22 g
3. 20.44 g
4. 4.0 g

2.8 10-3 mol of CO2 is left after removing 1021 molecules from its ' x ' mg sample. The mass of CO2 taken initially is Given: NA = 6.02 1023 mol-1

1. 98.3 mg
2. 196.2 mg
3. 150.4 mg
4. 48.2 mg

0.01 mole of an organic compound (X) containing 10\% hydrogen, on complete combustion produced 0.9 g H2O. Molar mass of (X) is g mol-1.

When 81.0 g of aluminium is allowed to react with 128.0 g of oxygen gas, the mass of aluminium oxide produced in grams is . (Nearest integer) Given : Molar mass of Al is 27.0 g mol-1 Molar mass of O is 16.0 g mol-1

Some CO2 gas was kept in a sealed container at a pressure of 1 atm and at 273 K. This entire amount of CO2 gas was later passed through an aqueous solution of Ca(OH)2. The excess unreacted Ca(OH)2 was later neutralized with 0.1 M of 40 mL HCl. If the volume of the sealed container of CO2 was x, then x is cm3 (nearest integer). [Given : The entire amount of CO2(g) reacted with exactly half the initial amount of Ca(OH)2 present in the aqueous solution.]

20 mL of 2 M NaOH solution is added to 400 mL of 0.5 M NaOH solution. The final concentration of the solution is 10-2 M. (Nearest integer)