Waec Chemistry 1989 Past Questions and Answers

Question 31:

• WAEC 1989

Which of the following is a condition for a spontaneous reaction?

A. ∆H -T is zero
B. ∆H-T∆ S is positive
C. ∆H-T∆ S is negative
D. ∆S is zero
E. ∆S is positive

Question 32:

• WAEC 1989

50cm 3 of a saturated solution of potassium trioxonitrate (V)at 40°C contains 5.05g of the salt. What is the solubility of potassium trioxonitrate (V) at 40°C? (KNO3 = 101)

A. 1.0 mol dm^-3
B. 1.5 mol dm^-3
C. 2.0 mol dm^-3
D. 2.5mol dm^-3
E. 5.0mol dm^-3

Question 33:

• WAEC 1989

The oxidation number of chlorine is + 1 in

A. KCIO ₃
B. CI ₂O ₇
C. ZnCI₂
D. HCI
E. NaCIO

Question 34:

• WAEC 1989

What is the voltage of the cell represented at Zn_(s) Zn ²⁺_(aq) /Cu²⁺_(aq) /Cu_(s) given that for Cu ²⁺_(aq)/ Cu _(s) E_o = 0.337V and for Zn²⁺_(aq) /Zn_(s)' E _o = -0.763V?

A. +0.426V
B. -0.426V
C. -0.337V
D. -1.10V
E. +1.10V

Question 35:

• WAEC 1989

(a) Write the chemical equation for the formation of named alkanoate.
(b)(i) What are the monomers of protein called?
(ii) Write the two functional groups present in the monomers named in (b)(i) above
(iii) State the type of reaction that leads to the formation of proteins from their monomers.