Question 576:

• JAMB 1989

The molar ratio of carbon to hydrogen of a volatile liquid compound is 1: 2. 0. 12 g of the liquid on evaporation at s.t.p. gave 32 cm³ of vapour. The molecular formula of the liquid is
[G.M.V =22.4 dm ³, C = 12, H = 1]

A. C ₃ H ₆
B. C ₄H ₈
C. C ₅C ₁₀
D. C ₆H ₁₂

Question 577:

• JAMB 1989

20.00 cm ³ of a solution containing 0.53 g of anhydrous Na₂CO₃ in 100 cm³ requires 25.00 cm³ of H₂SO₄ for complete neutralisation. The concentration of the acid solution in moles per dm is [H =1, C = 12, O = 16, Na =23, S = 32]

A. 0.02
B. 0.04
C. 0.06
D. 0.08

Question 578:

• JAMB 1989

The minimum volume of oxygen required for the complete combustion of a mixture of 10cm ³ of CO and 15 cm ³ of H ² is

A. 25.0cm³
B. 12.5 cm³
C. 10.0 cm³
D. 5.0cm³

Question 579:

• JAMB 1989

What is the partial pressure of hydrogen gas collected
over water at standard atmospheric pressure and 25 ^oC if the saturation vapour pressure of water at saturation vapour pressure of water is 23 mm Hg at that temperature?

A. 737 mm Hg
B. 763 mm Hg
C. 777 mm Hg
D. 783 mm Hg

Question 580:

• JAMB 1989

The atomic radius of Li, Na and K are 1: 33A, 1. 54A and 1. 96A res pectively. Which of the following explaqins this gradation in atomic radius?

A. Electropositivity decreases from Li to Na to K
B. Electronegativity decreases from Li to Na to K
C. The number of the electron shells increases from Li to Na to K
D. The elements are in the same period