SPM Science 2018, Paper 2 (Question 7 & 8)


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Question 7:
Diagram 7 shows a menu of Andrew’s breakfast.

Diagram 7

(a) Name the class of food for milk. [1 mark]

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Table 2 shows the calorific value for three types of food.

Table 2

(b) Andrew took 250 g of bread, 200 g of milk and 100 g of orange.
Calculate his total calories intake for breakfast. [1 mark]

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(c) Andrew is 15 years old, while his sister Amy is 25 years old.
Who requires a higher amount of calories daily?
Explain your answer. [2 marks]

(d) Amy did not take seafood in her diet for a long period of time.
(i) What is the health problem that she may suffer?
(ii) Explain your answer in 7(d)(i). [2 marks]

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Answer:
(a) Class of food for milk is Protein.

(b)
Calorific value of bread = 250 × 9.4 = 2350 kJ
Calorific value of milk = 200 × 13.7 = 2740 kJ
Calorific value of orange = 100 × 1.5 = 150 kJ
Total calories intake of breakfast for Andrew = 5240 kJ

(c)
Andrew requires a higher amount of calories daily.
Boys need more calories than girls.

(d)(i) Goitre

(d)(ii)
Lack of iodine


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Question 8:
Diagram 8 shows the deflection of radioactive radiation by an electrical field.

Diagram 8

(a) Name the radioactive radiation P. [1 mark]

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(b) Radioactive radiation Q is not deflected by the electrical field.
Give a reason for the observation. [1 mark]

(c) Which radiation has
(i) the highest penetration power?
(ii) the highest ionization power? [2 marks]

(d) Name one example of radioactive substance used in medical field. [2 marks]
Explain its usage.

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Answer:
(a)
Radiation P: Beta ray

(b)
Radioactive radiation Q is neutral to the electrical field

(c)(i)
Gamma rays has highest penetration power

(c)(ii)
Alpha ray has highest ionization power

(d)
Cobalt-60
Used to treat cancer