(a) What is surface tension?

(b) State two methods by which the surface tension of a liquid can be reduced.

Solve for x in the equation; \(\frac{1}{x} + \frac{2}{3x} = \frac{1}{3}\)

• A. 5
• B. 4
• C. 3
• D. 1

(a) Using a ruler and a pair of compasses only, (i) construct \(\Delta\) XYZ such that |XY| = 8 cm and < YXZ = < ZYX = 45°. (ii) locate a point P inside the triangle equidistant from XY and XZ and also equidistance from YX and YZ. (iii) construct a circle touching the three sides of the triangle (iv) measure the radius of the circle.

(b) The length of the sides of a hexagon are x - 5, 2x, 2x, 2x + 7, 2x and 2x - 1. If the perimeter is 144 cm, find the value of x.

(a) State two factors which can affect the rate of a chemical reaction.

(b) 0.72g of magnesium was added to different volumes of 2 mol. per dm\(^3\) hydrochloric acid. The volume of liberated was as measured at room temperature and pressure. The result of the experiment was as tabulated

Use the data in the table to plot a graph of the volume of hydrogen liberated against the volume of acid used.

(c) From the graph in (b) above, determine the volume of: (i) hydrogen that would be produced if 50 cm\(^3\) of the acid were added to 0.72g of magnesium.

(ii) the acid which must be added to 0.72 g of magnesium to produce 480 cm\(^3\) of hydrogen;

(iii) the acid needed exactly to dissolve 0.72 g of magnesium completely.

(d) Explain your answer to (c)(iii).

(e) From your answers to (c) above, deduce the: (i) volume of the acid which will dissolve 1 mole of magnesium completely. (Mg = 24)

(ii) volume of hydrogen that would be liberated if 1 mole of magnesium dissolves completely in the acid;

(iii) equation for the reaction between magnesium and hydrochloric acid. Show clearly how you arrived at you answers

Why is water often referred to as the universal solvent?

• A. Water is the most abundant substance on Earth
• B. Water is essential for all living organisms.
• C. Water is involved in many chemical reactions
• D. Water can dissolve a wide variety of substances due to its polar nature

Select the word that has the same pattern of stress as given word.

QUALITY?

• A. guarantee
• B. accepted
• C. bachelor
• D. related

Ada: wanja where are you going to in this ungodly hour of the night.

Wanja; i am heading towards my usual joint to enjoy myself.

Ada: which joint?

Wanja:XYZ night club, where i take marijuana and alcoholic breverages, i really want to be high tonight so that when people see me tomorrow, they will fear and respect me.

Ada: remember people who work under the influence of hard drugs and alcoholic breverages are prone to either psychiatric problems or premature death. softly young man, imbibe good natured character, you have the world at your feet and a destiny to fulfill. pray you will not be the architect of your own misfortune.

• A. national agency for food and drugs administration and control (NAFDAC)
• B. national orientation agency (NOA)
• C. national emergency management agency. (NEMA)
• D. national drug law enforcement agency (NDLEA)

On weekends, Mr. Baba likes to spend many hours working in his vegetable and flower gardens. Mrs. Baba spends her free time reading and listening to classical music. Both Mr. Baba and Mrs. Baba like to cook.

• A. Mr. Baba enjoys planting and growing vegetables.
• B. Mr. Baba does not like classical music.
• C. Mrs. Baba cooks the vegetables that Mr. Baba grows.
• D. Mrs. Baba enjoys reading nineteenth century novels

The periodic rise and fall in the intensity of sound produced whn two notes of nearly equal frequencies are sounded together is called? The periodic rise and fall in the intensity of sound produced whn two notes of nearly equal frequencies are sounded together is called?

• A. doppler effect
• B. beat
• C. interference
• D. resonance

Which of the following is not the the size of an exterior angle of a regular polygon?

• A. 15°
• B. 18°
• C. 20°
• D. 21°