UTME Chemistry 1992 JAMB Past Questions and Answers, Jamb, Pre-degree, Nursing, Waec, Neco

UTME Chemistry 1992 JAMB Past Questions and Answers

1. The pollutants that are likely to be present in an industrial environment are?

Options

A) H₂S,SO₂ and oxides of nitrogen

B) NH₃, HCI and CO

C) CO₂, NH₃ and H₂S

D) dust, NO and CI₂

The correct answer is A.

2. How many moles of (H+) are there in 1 dm³ of 0.5 M solution of H₂SO₄?

Options

A) 2.0 moles

B) 1.0 moles

C) 0.5 mole

D) 0.25 mole

The correct answer is B.

Explanation:

mole = (M x V ) / (1000cm₃) = (0.5 x 1000cm₃) = 0.5 moles
For H₂SO₄ → 2H⁺SO₄^2-
1 mole of H⁺ = 0.5 moles
2H⁺ = 2 x 0.5 mole = 1.0 mole

3. How many lone pairs of electron are there on the central atom of the H₂O molecules?

Options

A) 1

B) 2

C) 3

D) 4

The correct answer is B.

Explanation:

Ref___Google

The electron-dot structure of NH 3 places one pair of non-bonding electrons in the valence shell of the nitrogen atom. This means that there are three bonded atoms and one lone pair for a coordination number of four around the nitrogen, the same as occurs in H 2O.

4. ¹⁴₇N + X → ¹⁷₈O + ¹₁ H. In the above reaction, X is a?

Options

A) neutron

B) helium atom

C) litgium atom

D) deuterium atom

The correct answer is B.

5. wH₂SO₄ + xAI(OH)₃ → yH₂O + = zAI₂(SO₄)₃. The respective values of w.x.y and z in the equation above are?

Options

A) 2,2,5 and 1

B) 3,2,5 and 2

C) 3,2,6 and 1

D) 2,2,6 and 2

The correct answer is C.