WASSCE 2023 Integrated Science Past Questions And Answers

Answer all questions in this section.

Each question is followed by four options lettered A to D. Find the correct answer for each question

1. Which of the following symptoms is an indication of fungal infection in vegetable nursery?

A. Wilting of leaves

B. Swellings on stems

C. Rotting of stems

D. Curling of leaves

Solution: Rotting of stems is a common symptom of fungal infections in vegetable nurseries.

2. Which of the following statements about an atom is correct?

A. Protons out number electrons in a neutral atom

B. The L-shell is closest to the nucleus

C. Neutrons are found in the nucleus

D. The atomic number is greater than the mass number

3. A machine is rated 5.30 W. In how many seconds will it do 212.0 J of work?

A. 4.25 s

B. 0.03 s

C. 40.00 s

D. 25.00 s

Solution: Power = Work / Time. Therefore, Time = Work / Power = \( \frac{212.0 \, J}{5.30 \, W} = 40.00 \, s \).

4. Carbon (IV) oxide is used to extinguish fires because it

A. is fully oxidized.

B. occurs naturally.

C. is heavier than air.

D. is a reducing agent.

5. A deep litter house measuring 45.0 m by 2.2 m is stocked at the rate of one bird per \(0.25~m^{2}\). Determine the number of birds stocked.

A. 99 birds

B. 396 birds

C. 180 birds

D. 1584 birds

Solution: Area of the deep litter house = \(45.0 \, m \times 2.2 \, m = 99 \, m^{2}\). Number of birds = Area / Stocking rate per bird = \(99 \, m^{2} / 0.25 \, m^{2}/bird = 396\) birds.

6. An athlete weighs 750 N. Determine the athlete's mass. \([g=10~m~s^{-2}]\)

A. 750 kg

B. 375 kg

C. 75 kg

D. 7500 kg

Solution: Weight = mass \(\times\) acceleration due to gravity (\(W = mg\)). Therefore, mass = Weight / g = \( \frac{750 \, N}{10 \, m\,s^{-2}} = 75 \, kg \).

7. A child has a fever, runny nose, red sore eyes and a rash inside the mouth. Which of the following diseases is the child likely to be suffering from?

A. Whooping cough

B. Measles

C. Malaria

D. Poliomyelitis

8. An example of a leafy vegetable is

A. cabbage.

B. bean.

C. okro.

D. carrot.

9. It is compulsory to wear goggles when handling substances that

A. are poisonous.

B. are corrosive.

C. are highly flammable.

D. emit sparks.

10. Excess amino acids in the body undergo the process of

A. digestion.

B. detoxification.

C. deamination.

D. osmosis.

11. An electric heater rated 60 W is connected to 240 V mains. Determine the current in its filament.

A. 0.25 A

B. 4.00 A

C. 1440.00 A

D. 60.00 A

Solution: Power = Voltage \(\times\) Current (\(P = VI\)). Therefore, Current = Power / Voltage = \( \frac{60 \, W}{240 \, V} = 0.25 \, A \).

12. Which of the following statements about sea breeze is/are correct? It I. occurs during the night. II. occurs during the day. III. blows toward the sea.

A. Il only

B. I and III only

C. L only

D. II and III only

13. Nutrient required in large quantities by leafy vegetables is

A. nitrogen.

B. calcium.

C. potassium.

D. phosphorus.

14. The most effective way of controlling lice on fowls is by

A. spraying.

B. dipping.

C. dusting.

D. drenching.

15. In the vacuum flask, the vacuum between the polished walls minimizes heat transfer by

I. conduction.

II. radiation.

III. convection.

Which of the statements above are correct?

A. I and III only

B. II and III only

C. I and II only

D. I, II and III

16. Which of the following blood groups in humans does not contain antigen?

A. A

B. 0

C. B

D. AB

17. Which of the following diseases is caused by vitamin deficiency?

A. Night blindness

B. Hypertension

C. Tuberculosis

D. Dysentery

18. The normal period for a human pregnancy is

A. 52 weeks.

B. 32 weeks.

C. 28 weeks.

D. 40 weeks.

19. Which of the following pairs of crops is grown for their roots?

A. Cocoyam and onion

B. Cassava and carrot

C. Carrot and shallot

D. Cocoyam and shallot

20. The presence of methane and carbon (IV) oxide in the air is the main cause of

A. global warming.

B. high and low tides.

C. movement of air masses.

D. thunder storm.

21. Sickle-cell anaemia is an example of

A. sex-linkage.

B. blood grouping.

C. multiple alleles.

D. partial dominance.

22. Which of the following statements are correct about semiconductors? They I. are used to make transistors. II. do not obey Ohm's law. III. are group (IV) elements.

A. I, II and III

B. I and III only

C. I and II only

D. II and III only

23. An example of a simple machine is

A. sewing machine.

B. bicycle.

C. wheel and axle.

D. car.

24. During digestion, rennin in the stomach

A. provides acidic medium.

B. emulsifies fat.

C. coagulates milk protein.

D. digests carbohydrates.

25. It is more advantageous to use solar energy than fossil fuel energy because

A. fossil fuel energy is renewable.

B. solar energy causes pollution.

C. fossil fuel produces carbon (IV) oxide.

D. solar energy is renewable.

26. The protoplasm of a cell is made up of

A. cytoplasm and vacuole.

B. nucleus and vacuole.

C. cytoplasm and nucleus.

D. mitochondria and cell membrane.

27. Which of the following deductions cannot be made from the \(_{6}^{12}C2\)

A. Mass number of the element

B. Atomic number of the element

C. Number of neutrons in the nucleus

D. Relative atomic mass of the element

28. The size of the pupil of the eye is controlled by the

A. iris.

B. conjunctiva.

C. cornea.

D. lens.

29. Which of the following conditions could cause aflatoxin in groundnuts?

A. Growing groundnut in poor soils

B. Infection of groundnut plants by rosette disease

C. Excessive treatment of harvested pods with chemicals

D. Storage of pods of groundnut in humid conditions

30. Crop residue left on farms to conserve soil moisture are referred to as

A. waste materials.

B. stable mulch.

C. hay.

D. silage.

31. A body is more stable when its centre of gravity is

A. at the centre.

B. at its top.

C. outside the body.

D. close to the ground.

32. Ash from burnt plants is widely used in Ghana

A. as bleaching powder.

B. for preparing soap.

C. for preparing salt.

D. for improving soil texture.

33. The principle of flotation states that

A. a floating body displaces its own weight of fluid in which it floats.

B. a floating body experiences an upward force equal to its weight.

C. a body immersed in a fluid does not displace the fluid.

D. the upthrust on a floating body exceeds the body's weight.

34. Which of the following materials is magnetic?

A. Platinum

B. Brass

C. Cobalt

D. Aluminium

35. Biogas is produced from

A. anaerobic fermentation of organic waste.

B. aerobic fermentation of organic waste.

C. aerobic fermentation of inorganic waste.

D. anaerobic fermentation of inorganic waste.

36. The practice whereby shade is gradually removed from seedlings before transplanting is referred to as

A. rogueing.

B. hardening off.

C. thinning.

D. shading off.

37. The substance formed when carbon (IV) oxide is bubbled through lime water for a long time is

A. Ca(HCO₃)₂

B. Na₂CO₃

C. NaHCO₃

D. CaCO₃

Explanation: Initially, CO₂ reacts with lime water (\( \text{Ca(OH)}_2 \)) to form insoluble \( \text{CaCO}_3 \) (milky precipitate). Prolonged bubbling dissolves the precipitate into soluble calcium bicarbonate: \( \text{CaCO}_3 + \text{CO}_2 + \text{H}_2\text{O} → \text{Ca(HCO}_3\text{)}_2 \).

38. One advantage of weaning lambs early is that the

A. rams are not able to mate with the ewes easily.

B. ewes come on heat within a short period.

C. lambs become sexually matured easily.

D. mothers grow faster.

39. The manufacture of plastics involves the scientific process known as

A. crystallization.

B. fermentation.

C. vulcanization.

D. polymerization.

40. A solution contains 5.3 g of sodium trioxocarbonate (IV) per \(dm^{3}\). Determine its molarity. \([Na_{2}CO_{3}=106]\)

A. \(0.020~mol~dm^{-3}\)

B. \(0.050~mol~dm^{-3}\)

C. \(1.030~mol~dm^{-3}\)

D. 0.040 mol \(dm^{-3}\)

Solution: Molar mass of \(Na_{2}CO_{3} = 106 \, g/mol\). Moles of \(Na_{2}CO_{3} = \frac{\text{Mass}}{\text{Molar mass}} = \frac{5.3 \, g}{106 \, g/mol} = 0.05 \, mol\). Molarity = \( \frac{\text{Moles}}{\text{Volume in } dm^{3}} = \frac{0.05 \, mol}{1 \, dm^{3}} = 0.050 \, mol\,dm^{-3} \).

41. The energy output of a system is 40 J and the efficiency is 60%. Determine the energy input of the system.

A. 50.0 J

B. 66.7 J

C. 24.0 J

D. 75.4 J

Solution: Efficiency = \( \frac{\text{Energy output}}{\text{Energy input}} \times 100\% \). Energy input = \( \frac{\text{Energy output}}{\text{Efficiency}} \times 100\% = \left( \frac{40 \, J}{60\%} \right) \times 100\% = \left( \frac{40}{60} \right) \times 100 \, J \approx 66.67 \, J \). Rounded to one decimal place, this is 66.7 J.

42. Which of the following factors contribute to tidal waves experienced on the sea? I. The gravitational force of the sun and moon on the sea II. centripetal force created by the rotation of the earth around its axis III. occurrence of cyclones

A. I and II only

B. I and III only

C. I, II and III

D. II and III only

43. Myopia is an eye defect that makes a sufferer to

A. feel dizzy continuously.

B. view far away objects but not near objects.

C. view normally.

D. view near objects but not far away objects.

44. A quantity of NaCl was dissolved in \(100~cm^{3}\) of solution to obtain \(0.50~moldm^{-3}~NaCl\) solution. Determine the mass of NaCl used. \([NaCl=58.5]\)

A. 2.54 g

B. 25.40 g

C. 2.93 g

D. 29.35 g,

Solution: Molarity = \( \frac{\text{Moles}}{\text{Volume in } dm^{3}} \). Moles = Molarity \(\times\) Volume in \(dm^{3}\). Volume in \(dm^{3} = \frac{100~cm^{3}}{1000~cm^{3}/dm^{3}} = 0.1~dm^{3}\). Moles of NaCl = \( 0.50 \, mol\,dm^{-3} \times 0.1 \, dm^{3} = 0.05 \, mol \). Mass of NaCl = Moles \(\times\) Molar mass = \( 0.05 \, mol \times 58.5 \, g/mol = 2.925 \, g \). Rounded to two decimal places, this is 2.93 g.

45. The weather on earth is determined by changes in temperature, pressure and winds that take place in the

A. thermosphere.

B. stratosphere.

C. mesophere.

D. troposphere.

46. A farmer planted 2400 cuttings of cassava of which 85% survived grasscutter invasion. Determine the number of cassava plants that was destroyed.

A. 360

B. 155

C. 150

D. 204

Solution: Percentage of plants destroyed = \( 100\% - 85\% = 15\% \). Number of plants destroyed = \( 15\% \text{ of } 2400 = 0.15 \times 2400 = 360 \).

47. Which of the following statements about wind are correct? I. It is an air mass II. It moves from an area of high pressure to an area of low pressure. III. It moves from an area of low pressure to an area of high pressure

A. I, II and III

B. II and III only

C. I and III only

D. I and II only

48. Given that the Avogadro's constant is \(6.02\times10^{23}\), determine the number of atoms in 0.001 mol of aluminium metal.

A. \(6.02\times10^{26}\)

B. \(6.02\times10^{20}\)

C. \(3.01\times10^{20}\)

D. \(12.30\times10^{23}\)

Solution: Number of atoms = Moles \(\times\) Avogadro's constant = \( 0.001 \, mol \times 6.02\times10^{23} \, \text{atoms/mol} = 6.02\times10^{20} \) atoms.

49. Which of the following combinations of elements do all carbohydrates contain?

A. Sulphur, carbon, hydrogen and oxygen

B. Carbon, phosphorus, oxygen and hydrogen

C. Carbon, hydrogen and nitrogen

D. Carbon, hydrogen and oxygen

50. Setts are planting materials used for the cultivation of

A. ginger.

B. pineapple.

C. radish.

D. yam.