Neco Chemistry Past Questions and Answers

Question 21:

• NECO 2001

20 cm³ of 0.09 mol dm³ solution of tetraoxosuiphate (Vi) acid requires 30cm³ of sodium hydroxide solution for complete neutralization. The molar concentration of sodium hydroxide is [H = 1; S = 32; 0 = 16; Na = 23]

A. 0.03 mol dm³
B. 0.12 mol dm³
C. 0.27 mol dm³
D. 0.45 mol dm³
E. 0.90 mol dm³

Question 22:

• NECO 2001

The decreasing order of the oxidising power of the halogens is ____________

A. Br>I>Cl>F
B. F>I>Cl>Br
C. F>Cl>Br>l
D. I>Br>Cl>F
E. Cl>Br>F>I

Question 23:

• NECO 2001

Which statement BEST describes the process of oxidation?

A. Addition of hydrogen
B. Loss of oxygen
C. Decrease in oxidation number
D. Loss of electrons
E. Gain of elections.

Question 24:

• NECO 2001

Animal charcoal differs from wood charcoal in that it ____________

A. Has a dark colour
B. Has a high carbon content
C. Is a good absorbent
D. Is crystalline.
E. Is rich in phosphate content

Question 25:

• NECO 2001

The atomic number of iron is 56. The number of unpaired electrons in the Fe3+ ion is ____________

A. 1
B. 2
C. 3
D. 4
E. 5