A metallic ion Z²⁺ with an inert gas structure contains 18 electrons. How many protons are contained in this ion?

• A. 20
• B. 18
• C. 16
• D. 2

In the diagram, IG is parallel to JE, JEF = 120° and FHG = 130°, find the angle marked t

• A. 40°
• B. 70°
• C. 80°
• D. 100°

Islam was introduced in Kano during the reign of

• A. Sarkin Kano Ibrahim Dabo
• B. Sarkin Kano Kanajeji
• C. Sarkin Kano Muhammadu Rumfa
• D. Sarkin Kano Yaji.

Na₂S₂O₃(aq) + 2HCl(aq) → 2NaCl(aq) + H₂O(l) Which of the following would introduce the greatest increase in the rate of the chemical reaction above?

• A. An increase in temperature and decrease in the concentration of the reactant
• B. A decrease in the volume and increase in the pressure of the reactant
• C. A decrease in the temperature and an incease in the concentration of the reactant
• D. An increase in temperature and an increase in the concentration of the reactant

(a) State three conclusions that can be drawn from Rutherford's experiment on the scattering of alpha particles by a thin metal foil in relation to the structure of the atom

The diagram below illustrates th3 energy levels of an electron in an atom. If an excited electron moves from n\(_2\) to n\(_\theta\), calculate the:

(i) frequency;

(ii) wavelength of the emitted radiation. [ h = 6.6 x 10\(^{-34}\) Js; le V = .6 x 10\(^{-19}\) J; C = 3.0 x 10\(^8\) ms\(^{-1}\)]

(c) The following nuclear equations represent two types of radioactivity.

\(^{226}_{88}R_a \to ^{222}_{86}R_n + ^a_2a\) (Equation A)

\(^{14}_7N + ^4_2a \to ^{17}_8O + ^1_1p\) (Equation B)

Identify each type and explain briefly the difference between them

Communism was popularized by

• A. Karl Marx and Fredrick Engels
• B. Max Weber and Aristotle
• C. Plato and Socrates
• D. Harold Laski and Jean Bodin

Which of the following is not a feature of a self-service store?

• A. it is found mainly in urban areas
• B. it offers steady employment opportunities
• C. Goods carry price tags
• D. it operates on a large floor space

Which of the following problem does not cause wastage of farm produce?

• A. Use of crude farm tools
• B. Poor transportation
• C. Inadequate processing facilities
• D. Inadequate storage facilities

Geometric isomerism can exist in

• A) hex-3-ene
• B) hexane
• C) prop-l-ene
• D) 3-methyl but -l-ene

From the words lettered A to D below each of the following sentences, choose the word that is nearest in meaning to the underlined word.

All that was left after the riot were thecharred remains of the victims.

• A. burnt
• B. black
• C. broken
• D. scattered