271.

Commercial sample of H₂O₂ is labeled as 10 V. Its % strength is nearly

• 3

• 6

• 9

• 12

The system that contains the maximum number of atoms is

• 4.25 g of NH₃

• 8 g of O₂

• 2g of H₂

• 4g of He

The volume of ethyl alcohol ( density 1.15 g/cc) that has to be added to prepare 100 cc of 0.5 M ethyl alcohol solution in water is 

• 1.15 cc

• 2 cc

• 2.15 cc

• 2.30 cc

Which one of the following is wrong about molecularity of a reaction?

• It may be whole number or fractional

• It is calculated from reaction mechanism

• It is the number of molecules of the reactants taking part in a single step chemical reaction

• It is always equal to the order of elementary reaction

The amount of the heat released when 20 mL 0.5 M NaOH is mixed with 100 mL 0.1 M HCl is × kJ. The heat of neutralisation is

• -100 x kJ/mol

• -50 x kJ/mol

• + 100 x kJ/mol

• +50 x kJ/mol

2 g of metal carbonate is neutralised completely by 100 mL of 0.1 N HCl. The equivalent weight of metal carbonate is

• 50

• 100

• 150

• 200

If the molecular wt. of Na₂SO₃ and I₂ are M₁ and M₂ respectively then what will be the equivalent weight of Na₂SO₃ and I₂ in the following reaction?

2S₂O${}_3^{2-}$ + I₂ → S₄O${}_6^{2-}$ + 2I^-

• M₁, M₂

• M₁, M₂ /2

• 2M₁, M₂

• M₁, 2M₂

The normality of 30 volume H₂O₂ is

• 2.678 N

• 5.336 N

• 8.034 N

• 6.685 N

The weight of oxalic acid that will be required to prepare a 1000 mL (N/20) solution is

• 126/100 g

• 63/40 g

• 63/20 g

• 126/20 g

Gaseous benzene reacts with hyodrogen gas in presence of a nickel catalyst to form gaseous cyclohexane according to the reaction, 

C₆H₆ (g) + 3H₂ (g) → C₆H₁₂ (g)

A mixture of C₆H₆ and excess H₂ has a pressure of 60 mm of Hg in an unknown volume. After the gas had been passed over a nickel catalyst and all the benzene converted to cyclohexane, the pressure of the gas was 30 mm of Hg in the same volume at the same temperature. The fraction of C₆H₆ (by volume) present in the original volume is

• 1/3

• 1/4

• 1/5

• 1/6