The volume of oxygen liberated at STP from 15 mL of 20 volume H₂O₂ is

• 100 mL

• 200 mL

• 300 mL

• 400 mL

Calculate the molality of a solution that contains 51.2 g of naphthalene (C₁₀H₈) in 500 mL of carbon tetrachloride. The density of CCl₄ is 1.60 g/mL

• 0.250 m

• 0.500 m

• 0.750 m

• 0.840 m

When 2.46 gm of a hydrated salt (MSO₄xH₂O) is completely dehydrated, 1.20 gm of anhydrous salt is obtained. If the molecular weight of anhydrous salt is 120 gm mol^-1, what is the value of x?

• 2

• 7

• 4

• 6

An organic compound contains 90% carbon and 10% hydrogen by mass. Its empirical formula is

• C₂H₄

• C₃H₆

• C₃H₈

• C₃H₄

65.

How many molecules of CO₂ are formed when one milligram of 100% pure CaCO₃ is treated with excess hydrochloric acid?

• 6.023 × 10²³

• 6.023 × 10¹⁸

• 6.023 × 10²¹

• 6.023 × 10²²

5.0 g of sodium hydroxide (molar mass 40 g mol^-1) is dissolved in little quantity of water and the solution is diluted upto 100 ml. What is the molarity of the resulting solution?

• 0.1 mol dm^-3

• 1.0 mol dm^-3

• 0.125 mol dm^-3

• 1.25 dm^-3

0.02 mole of [Co(NH₃)₅Br]Cl₂ and 0.02 mole of [Co(NH₃)₅Cl]SO₄ are present in 200 cc of a solution X. The number of moles of the precipitates Y and Z that are formed when the solution X is treated with excess barium chloride are respectively.

• 0.02, 0.02

• 0.01, 0.02

• 0.02, 0.04

• 0.04, 0.02

The maximum prescribed concentration of cadmium in drinking water in ppm is

• 0.05

• 3

• 2

• 0.005

A 100% pure sample of a divalent metal carbonate weighing 2 g on complete thermal decomposition releases 448 cc of carbon dioxide at STP. The equivalent mass of the metal is

• 40

• 20

• 28

• 12

Molar heat capacity of aluminium is 25 JK^-1 mol^-1. The heat necessary to raise the temperature of 54 g of aluminium (atomic mass 27 g mol^-1) from 30°C to 50°C is

• 1.5 kJ

• 0.5 kJ

• 1.0 kJ

• 2.5 kJ