Solubility - Jamb Chemistry Past Questions and Answers

Question 21:

• JAMB 1983

A piece of burning sulphur will continue to burn in a gas jar of oxygen to give misty fumes which readily dissolved in water. The resulting liquid is

A. Sulphur (VI) trioxide
B. Tetraoxosulphate (VI) acid
C. Trioxosulphate (IV) acid
D. Dioxosulphate (II) acid
E. Hydrogen sulphide

Question 22:

• JAMB 1983

3. 06 g of a sample of potassium trioxochlorate (V) (KCIO) was required to make a saturated solution with 10cm³ of water at 25^oC. The solubility of the salt at 25^oC is [K =39, Cl = 35.5, O = 16]

A. 5.0 moles dm³
B. 3.0 moles dm³
C. 2.5 moles dm³
D. 1.0 molesv
E. 0.5 moles dm³

Question 23:

• JAMB 1983

Which of the following solutions will give a white precipitate with barium chloride solution and a green flame test?

A. Na₂SO₄
B. CuSO₄
C. CaSO₄
D. CaCI₂
E. (NH₄)₂SO₄

Question 24:

• JAMB 1984

Naphthalene when heated melts at 354 K (81 ^oC). At this temperature the molecules of naphthalene

A. Decompose into smaller molecules
B. Change their shape
C. Are oxidized by atmospheric oxygen
D. Contract
E. Become mobile as the inter molecular forces are broken

Question 25:

• JAMB 1984

Sodium hydroxide (NaOH) pellets are

A. Deliquescent
B. Hygroscopic
C. Efflorescent
D. Hydrated
E. Fluorescent