What is the basicity of tetraoxosulphate (VI) acid?

• A) 2
• B) 1
• C) 3
• D) 4

50 cm³ of carbon (II) oxide was exploded with 150 cm³ of air containing 20% oxygen by volume. Which of the reactants was in excess?

• A. Carbon (II) oxide
• B. Carbon (IV) oxide
• C. Oxygen
• D. Nitrogen

The scientist who stated that matter can be converted into energy is?

• A. Boyle
• B. Lavoiser
• C. Avogadro
• D. Einstein

A given volume of methane diffuses in 20 seconds. How long will it take the same volume of sulphur (IV) oxide to diffuse under the same conditions? [CH4 = 16; SO2 = 64]

• A. 5 seconds
• B. 20 seconds
• C. 40 seconds
• D. 60 seconds

The colour of litmus in an alkaline medium is

• A) Red
• B) Yellow
• C) Pink
• D) Blue

An atom W has 17 electrons and 18 neutrons. Which of the following representations of the atom is correct?

• A.¹⁷₁₈W
• B.¹⁸₁₇W
• C.³⁵₁₇W
• D.³⁵₁₈W

Which of the following pollutants is associated with brain damage?

• A) Carbon (ll) oxide
• B) Radioactive fallout D) Sulphus (lV) oxide
• C) Biodegradable waste
• D) Sulphus (lV) oxide

How many neutrons are present in atom with mass number and atomic number 37 and 17 respectively?

• A. 18
• B. 20
• C. 37
• D. 17

Magnesium (IV) oxide is known to hasten the decomposition of hydrogen peroxide. Its main action is to?

• A. increase the surface area of the reactants
• B. increase the concntration of the reactants
• C. lower the activation energy for the reaction
• D. lower the heat of reaction, ∆H, for the reaction

If 10 cm³ of distilled water is added to 10cm³ of an aqueous salt solution, the concentration of the solution

• A. increases
• B. decreases
• C. remains constant
• D. doubles