Chemistry 2010 Waec Past Questions and Answers

Question 36 :

• WAEC 2010

Compound N reacts with sodium metal to produce a gas that gives a 'pop' sound with a burning splint N also react with ethanoic acid to give a sweet smelling liquid. Compound N is an

A. Alkanol
B. Alkanoate
C. Alkane
D. Alkanoic acid

Question 37 :

• WAEC 2010

The main function of limestone in the blast furnance is to

A. Act as a reducing agent
B. Act as a catalyst
C. Remove impurities
D. Supply carbon (IV) oxide

Question 38 :

• WAEC 2010

Which of the following substances cannot be classified as a heavy chemical?

A. AgNO₃
B. CaO
C. CaOCI₂
D. H₂SO₄

Question 39 :

• WAEC 2010

Which of the following metals exists as liquid at ordinary temperature?

A. Copper
B. Gold
C. Mercury
D. Silver

Question 40 :

• WAEC 2010

(a) i) Give the name and nature of the radiations that are emitted during radioactivity.
ii) State two differences between chemical reaction and nuclear reaction.
iii) Balance the following nuclear reactions and identify X and Y.
I. \(^{212}_{84} PO\) \(\to\) \(^{208}_{82} Pb\) + X
II \(^{137}_{55}Cs\) \(\to\) \(^{137}_{55}Ba\) + Y
(b) The electron configuration of an element X is: 1s\(^2\) 2s\(^2\) 2p\(^6\) 3s\(^2\) 3p\(^5\)
(i) Deduce the atomic number of X.
(ii) To what group does X belong?
(iii) Give two properties of the group to which the element X belong.
(iv) Identify element X by name.
(v) Write a balanced equation to represent the reaction between the element X and hot concentrated NaOH.

(c)(i) Explain why: I. graphite is used as a lubricant; II. diamond is used as an industrial cutting tool.
(ii) Write an equation to represent the reaction between aqueous HCI and NH\(_3\) solution.
(iii) Name the type of reaction represented by the equation.