Some Basic Concepts of Chemistry

What is the total number of moles of H₂SO₄ needed to prepare 5.0 L at a 2.0M solution of H₂SO₄ ?

• 2.5

• 5.0

• 10

• 20

In stoichiometric defect, the ratio of positive and negative ions as indicated by chemical formula of the compound

• decreases

• increases

• changes by a factor of 2

• remains same

Density of a 2.05 M solution of acetic acid in water is 1.02 g/mL. The molality of the solution is

• 2.28 mol kg^-1

• 3.28 mol kg^-1

• 0.44 mol kg^-1

• 1.14 mol kg^-1

Consider the following reaction,

(CH₃)₃CCl + OH^- → (CH₃)₃C-OH + Cl^-

If OH^- does not take part in slow step, the molecularity and order of the reaction are respectively,

• 2, 2

• 2, 1

• 1, 2

• 1, 1

When one litre one molar sulphuric acid solution is diluted with 5 L water, the normality of the obtained solution is

• 0.2 N

• 0.33 N

• 10 N

• 5 N

The normality of 10 L volume H₂O₂ is

• 0.176

• 0.88

• 1.78

• 3.52

Sodium bicarbonate on heating decomposes to form sodium carbonate, CO₂ and water. If 0.2 moles of sodium bicarbonate is completely decomposed, how many moles of sodium carbonate is formed?

• 0.1

• 0.2

• 0.05

• 0.025

250 mL of a Na₂CO₃ solution contains 2.65 g of Na₂CO₃ 10 mL of this solution is added to x mL of water to obtain 0.001 M Na₂CO₃ solution.The value of x is (molecular weight of Na₂CO₃ = 106)

• 1000 mL

• 990 mL

• 9990 mL

• 90 mL

Which of the following represents the smallest quantity?

• 1230g

• 1.230 × 10^-4 g

• 1.230 × 10^-6 kg

• 1.230 × 10⁴ µg

How is 0.0120 written as a scientific notation?

• 120 × 10^-4

• 1.2 × 10^-2

• 12 × 10^-3

• 12.0 × 10^-3