4g of copper was dissolved in concentrated nitric acid. The copper nitrate solution on strong heating gave 5 g of its oxide. The equivalent weight of copper is

• 23

• 32

• 12

• 20

The volume of water to be added to $\frac{\mathrm{N}}{2}$ to prepare 500 mL of $\frac{\mathrm{N}}{10}$ solution is

• 450 mL

• 100 mL

• 45 mL

• 400 mL

The equivalent weight of a certain trivalent element is 20. Molecular weight of its oxide is

• 152

• 56

• 168

• 68

164.

What is the volume of "20 volume H₂O₂" required to get 5000 cm³ of oxygen at STP?

• 250 cm³

• 50 cm³

• 100 cm³

• 125 cm³

Molarity of 0.2 N H₂SO₄ is

• 0.2

• 0.4

• 0.6

• 0.1

An atom of an element A has three electrons in its outermost orbit and that of B has six electrons in its outermost orbit. The formula of the compound between these two will be

• A₃B₆

• A₂B₃

• A₃B₂

• A₂B

The decomposition of a certain mass of CaCO₃ gave 11.2 dm³ of CO₂ gas at STP. The mass of KOH required to completely neutralise the gas is :

• 56 g

• 28 g

• 42 g

• 20 g

Molarity of a given orthophosphoric acid solution is 3M. It's normality is

• 9 N

• 0.3 N

• 3 N

• 1 N

Gram molecular volume of oxygen at STP is

• 3200 cm³

• 5600 cm³

• 22400 cm³

• 11200 cm³

What is the equivalent weight of SnCl₂ in the following reaction?

SnCl₂ + Cl₂ → SnCl₄

• 95

• 45

• 60

• 30