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SPM Science 2017, Paper 2 (Question 7 & 8)

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Question 7:
Diagram 7.1 shows various use of synthetic rubber.

Diagram 7.1

(a) Based on Diagram 7.1, state the major use of synthetic rubber. [1 mark]

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(b) State two characteristics of synthetic rubber which is used to make shoe soles. [2 marks]

(c) Diagram 7.2 shows the formation of vulcanised rubber.

Diagram 7.2

(i) What is process R? [1 mark]
(ii) Draw the structure of vulcanised rubber in the space provided on Diagram 7.2. [1 mark]
(iii) State one function of sulphur in the formation of vulcanised rubber. [1 mark]

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Answer:
(a) Tyre

(b)
1. Heat resistant
2. Hard
3. Water resistant
(Choose any two)

(c)(i) Vulcanisation

(c)(ii)



(c)(iii) To prevent rubber polymer from sliding with each other



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Question 8:
Diagram 8.1 shows word equation of the soap making process.

Diagram 8.1

(a) What is the name of the soap making process? [1 mark]

(b) Give one example of substance X. [1 mark]

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(c) Diagram 8.2 shows the structure of a soap molecule.
Name the part Y and Z in the boxes provided in Diagram 8.2 using the following words given. [2 marks]

Diagram 8.2

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(d) A student found that her clothes stained with dirt.
Arrange the following cleansing actions of soap in the correct sequence in the boxes provided. [2 marks]



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Answer:
(a) Saponification

(b) Palm oil

(c)
Y: Hydrophilic
Z: Hydrophobic

(d)



SPM Science 2017, Paper 2 (Question 5 & 6)

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Question 5:
Diagram 5.1 shows an experiment to study a fermentation process.

Diagram 5.1

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The word equation below represents the chemical reaction in Diagram 5.1.


(a) Based on the experiment,
(i) What is X?
(ii) State one characteristic of X. [2 marks]

(b) Mark (\/) on the element that can be found in X. [1 mark]



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(c) Name one substance which can be used to replace glucose solution in Diagram 5.1. [1 mark]

(d) What is the effect of excessive consumption of alcohol to organ S and T shown in Diagram 5.2? [2 marks]

Diagram 5.2

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Answer:
(a)(i)
Alcohol (Methanol/ Ethanol/ Butanol/ Pentanol/ Propanol)

(a)(ii)
Colourless/ Dissolves in water/ Flammable
(Choose one)

(b) Carbon

(c) Any fruit juice.

(d)(i)
Effect of excessive consumption of alcohol to organ S: Brain damage/ Imbalanced/ Blurred vision (Choose one)

(d)(ii)
Effect of excessive consumption of alcohol to organ T: Liver inflammation/ Scarring of liver/ Cirrhosis (Choose one)



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Question 6:
Diagram 6.1 and Diagram 6.2 show food labels found on two different brands of chilli sauce.

Diagram 6.1


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Diagram 6.2

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(a) Based on Diagram 6.1 and Diagram 6.2,
(i) Which food label follows the Food Regulations 1985?
(ii) Give one reason for your answer in 6(a)(i). [2 marks]

(b)(i) Which substance is used as preservative in brand W chilli sauce?
(ii) State one function of the preservative in 6(b)(i). [2 marks]

(c) Both brands use artificial colouring in their product.
Do you agree with the use of artificial colouring in food?
Justify your answer. [2 marks]

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Answer:
(a)(i) Chilli sauce brand V

(a)(ii) Has expiry date.

(b)(i) Vinegar/ Sodium benzoate

(b)(ii) Prevent growth of bacteria

(c)
Agree
- Make food more attractive
Or
Disagree
- Cause cancer/ Damage kidney

SPM Science 2017, Paper 2 (Question 3 & 4)

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Question 3:
A student carried out a study to determine the effect of phosphorus on the growth of orchid plants. The student used aerophonic method, by spraying different fertilisers’ solution on orchid plant P and Q twice a week.
Diagram 3 shows the result after two months.

Diagram 3

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(a) Based on your observation, state one difference between orchid plant P and Q. [1 mark]

(b) In your opinion, what type of fertiliser is used on orchid plant P and Q? [2 marks]

(c) State one hypothesis for this study. [1 mark]

(d) Predict what will happen to the orchid plant P if the student replaced the fertiliser solution with tap water for three months. [1 mark]

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Answer:
(a) Orchid plant P has more/ longer roots.

(b)
Orchid P: Fertilisers with phosphorus
Orchid Q: Fertilisers without phosphorus

(c) Orchid plants need phosphorus for healthy growth/ more or longer roots/ big flower.

(d) Orchid plant P growth stunted.

SPM Science 2017, Paper 2 (Question 1 & 2)

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Question 1:
Diagram 1 shows an experiment to study the transmission of pressure in liquid by hydraulic system. A weight is added on the big piston’s syringe. The suitable weights are added on the small piston’s syringe until both pistons are at the same level. The weight added represents the force acting on both pistons.

Diagram 1

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The result of the experiment is shown in Table 1.

Table 1

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(a) Based on the result in Table 1, draw a graph to show the force acting on the small piston against the force acting on the big piston on the graph paper provided. [2 marks]



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(b) Based on the graph in 1(a), what is the force acting on the small piston if the force acting on the big piston is 8 N? [1 mark]

(c) What is the factor being fixed in this experiment? [1 mark]

(d) Name an appliance that uses the same principle as in Diagram 1. [1 mark]

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Answer:
(a)


(b) 3.2 N (± 0.1)

(c) Volume of water

(d) Hydraulic brake / Hydraulic jack



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Question 2:
Diagram 2 shows an experiment to study the effect of light on the growth of bacteria.
Diagram 2

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The condition of the nutrient broth in test tube P and Q is observed after three days.
The result of this experiment is recorded in Table 2.

Table 2

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(a) State one observation on the nutrient broth which has been kept in the black box for three days. [1 mark]

(b) State one inference for this experiment. [1 mark]

(c) State the variables in this experiment. [2 marks]
(i) Manipulated variable
(ii) Responding variable

(d) Based on this experiment, state the operational definition of bacteria. [1 mark]

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Answer:
(a) Condition of nutrient broth is cloudy.

(b) The bacteria grow actively in dark condition.

(c)(i) Presence of light

(c)(ii) Condition of nutrient broth

(d) Bacteria is a microorganism that caused the condition of nutrient broth turns cloudy.

Derive By First Principle – Example 1

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Solving Equation of Index Number

Example

Derive the equation $$y = {x^2} + \frac{3}{x}$$ by using first principle.

$$\eqalign{ & y = {x^2} + \frac{3}{x} \cr & \frac{{dy}}{{dx}} = \mathop {\lim }\limits_{\delta x \to 0} \frac{{\delta y}}{{\delta x}} \cr & = \mathop {\lim }\limits_{\delta x \to 0} \frac{{\left( {y + \delta y} \right) – y}}{{\delta x}} \cr & = \mathop {\lim }\limits_{\delta x \to 0} \frac{{\left[ {{{\left( {x + \delta x} \right)}^2} + \frac{3}{{x + \delta x}}} \right] – \left[ {{x^2} + \frac{3}{x}} \right]}}{{\delta x}} \cr & = \mathop {\lim }\limits_{\delta x \to 0} \frac{{{x^2} + 2x\delta x + \delta {x^2} – {x^2} + \frac{3}{{x + \delta x}} – \frac{3}{x}}}{{\delta x}} \cr & = \mathop {\lim }\limits_{\delta x \to 0} \frac{{2x\delta x + \delta {x^2}}}{{\delta x}} + \frac{{\frac{{3x – 3(x + \delta x)}}{{x(x + \delta x)}}}}{{\delta x}} \cr & = \mathop {\lim }\limits_{\delta x \to 0} 2x + \delta x + \frac{{ -3 \delta x}}{{x(x + \delta x)}} \times \frac{1}{{\delta x}} \cr & = \mathop {\lim }\limits_{\delta x \to 0} 2x + \delta x + \frac{{ – 3}}{{x(x + \delta x)}} \cr & = 2x – \frac{3}{{{x^2}}} \cr} $$

$$\frac{{dy}}{{dx}} = \mathop {\lim }\limits_{\delta x \to 0} \frac{{\delta y}}{{\delta x}}$$

Selesaikan Persamaan Nombor Indeks – Contoh 1

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Selesaikan Persamaan Nombor Indeks

Contoh

Selesaikan persamaan 5x-1 + 5x+2 = 3150

$$\eqalign{
& {5^{x – 1}} + {5^{x + 2}} = 3150 \cr
& \frac{{{5^x}}}{5} + {5^x} \times {5^2} = 3150 \cr
& \frac{{{5^x}}}{5} + \frac{{125 \times {5^x}}}{5} = 3150 \cr
& 126 \times {5^x} = 5 \times 3150 \cr
& {5^x} = \frac{{5 \times 3150}}{{126}} \cr
& {5^x} = 125 = {5^3} \cr
& x = 3 \cr} $$

$$\eqalign{
& {a^m} \times {a^n} = {a^{m + n}} \cr
& {a^m} \div {a^n} = \frac{{{a^m}}}{{{a^n}}} = {a^{m – n}} \cr
& {\text{Hence}} \cr
& {5^{x – 1}} = {5^x} \div 5 = \frac{{{5^x}}}{5} \cr
& {5^{x + 2}} = {5^x} \times {5^2} \cr} $$

Solving Equation of Index Number – Example 1

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Solving Equation of Index Number

Example

Solve the equation 5x-1 + 5x+2 = 3150

$$\eqalign{
& {5^{x – 1}} + {5^{x + 2}} = 3150 \cr
& \frac{{{5^x}}}{5} + {5^x} \times {5^2} = 3150 \cr
& \frac{{{5^x}}}{5} + \frac{{125 \times {5^x}}}{5} = 3150 \cr
& 126 \times {5^x} = 5 \times 3150 \cr
& {5^x} = \frac{{5 \times 3150}}{{126}} \cr
& {5^x} = 125 = {5^3} \cr
& x = 3 \cr} $$

$$\eqalign{
& {a^m} \times {a^n} = {a^{m + n}} \cr
& {a^m} \div {a^n} = \frac{{{a^m}}}{{{a^n}}} = {a^{m – n}} \cr
& {\text{Hence}} \cr
& {5^{x – 1}} = {5^x} \div 5 = \frac{{{5^x}}}{5} \cr
& {5^{x + 2}} = {5^x} \times {5^2} \cr} $$

Derived Quantities

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1.2.2 Derived Quantities

  1. A derived quantity is a Physics quantity that is not a base quantity. It is the quantities which derived from the base quantities through multiplying and/or dividing them.
  2. For example, speed is define as rate of change of distance, Mathematically, we write this as Speed = Distance/Time. Both distance and time are base quantities, whereas speed is a derived quantity as it is derived from distance and time through division. Example
    (Speed is derived from dividing distance by time.)
  3. Belows are the derived quantities that you need to know in SPM. You need to know the equation of all the quantities, so that you can derive their unit from the equation.
  4. If you find it difficult to memorise all these equation, you can skip it now because you are going to learn all of them in the other chapter. 

Base Quantities

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1.2.1 Base Quantities

Physical Quantity

  1. A physical quantity is a quantity that can be measured.
  2. A physical quantity can be divided into base quantity and derived quantity.

Base Quantities

  1. Base quantities are the quantities that cannot be defined in term of other physical quantity.
  2. The base quantities and its units are as in the table below:
TIPS: In SPM, you MUST remember all 5 base quantities and its SI unit.

Introduction to Physics

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Introduction to Physics

1.1.1 Understanding Physics

Physics is a branch of science that studies the

  1. natural phenomena
  2. properties of matter
  3. energy

Field of study in Physics

The field of studies in Physics including

  1. Motion
  2. Pressure
  3. Heat
  4. Light
  5. Waves
  6. Electricity
  7. Magnetism and electromagnetism
  8. Electronics
  9. Nuclear Physics