Post Utme Ahmadu Bello University Chemistry Past Questions and Answers

Question 11:

In the reaction between sodium hydroxide and sulphuric acid solutions. What volume of 0.5molar sodium hydroxide would exactly neutralize 10cm3of 1.25molar sulphuric acid?

A. 5cm³
B. 10cm³
C. 20cm³
D. 25cm³
E. 50cm³

Question 12:

A small quantity of solid ammonium chloride \((NH_4Cl)\) was heated gently in a test tube. The solid gradually disappear to produce a mixture of two gases later a white cloudy deposit was observed on the cooler part of the test tube. The ammonium chloride is said to have undergone ____________

A. Distillation
B. Sublimation
C. Precipitation
D. Evaporation
E. Decomposition

Question 13:

Elements P, Q, R, S have 6, 11, 15, & 17 electrons respectively.

Therefore, ____________

A. P will form an electrovalent bond with R
B. Q will form a covalent bond with S
C. R will form an electrovalent bond with S
D. Q will form an electrovalent bond with S
E. Q will form a covalent bond with R

Question 14:

An element X forms the following compounds with chlorine \(NCl_4\), \(XC_3\). \(XC_2\) this illustrates the ____________

A. Law of multiple proportions
B. Law of chemical proportions
C. Law of simple proportion
D. Law of conservation of mass
E. Law of definite proportion

Question 15:

The oxidation state of chlorine in potassium chlorate is ____________

A. 11
B. 12
C. 13
D. 15
E. 17