Form 2 Workbook answers

Form 2 Workbook answers

Ch9:
https://drive.google.com/file/d/1x-hwreyjXkfxkVzt8lq6t19RR6Wv858l/view?usp=sharing

Ch10:
https://drive.google.com/file/d/1Auvf_zp2V-bRUU4M2bKPOJZpmLMByJEt/view?usp=sharing

Ch11:
https://drive.google.com/file/d/1TEzC-ftSxGryWifg1ZwXtDCHmC0DUlxb/view?usp=sharing

Workbook Answers Chapter 8

Section 8.1 (P.51)

A. Concept checking

1.          False

2.          True

3.          False

4.          True

5.          True

B. Multiple choice

1.     (a)    electrical conductors

(b)    electrical insulators

2.     (a)    closed

        (b)    open

C. Question

1.     (a)    electrical insulator

(b)    electrical conductor

(c)    electrical insulator

(d)   electrical conductor

(e)    electrical insulator

(f)    electrical insulator

(g)    electrical insulator

(h)    electrical conductor

(i)     electrical conductor

2.

3.     (a)    (i)     will not

                (ii)    do not form

        (b)    (i)     will

                (ii)    form a closed circuit

        (c)    (i)     will

                (ii)    the bulb, the dry cells and the wires form a closed circuit

        (d)   (i)     will not

                (ii)    electrical energy in the circuit

4.     No. The wheels of the tram are connected with the power supply through the rails, and the circuit is complete. (or other reasonable answers)

Section 8.2 & 8.3 (P.54)

A. Multiple choice

1.     (a)    ampere

        (b)    volt

2.     free electrons

3.     1.5

4.     (a)    ammeter

        (b)    voltmeter

5.     larger

B. Question

1.     (a)    dry cell

(b)    wire

(c)    free electrons

Section 8.5
A. Multiple choice p.60-61
1. D
2. C
3. B
4. C

B. Question p.61-62
1.
(a) dry cell
(b) battery
(c) bulb
(d) ammeter
(e) voltmeter
(f) resistor
(g) rheostat
(h) switch

Integrated Exercise
A. Concept checking p.79
1. False
2. True
3. False
4. False
5. True
6. True

B. Multiple choice p.80-83

1. B

2. D

3. B

4. C

5. B

6. D

7. D

8. C

9. B

Quick Review
1. Electric current, voltage and resistance p.90
(a) open
(b) closed
(c) voltage
(d) larger
(e) resistance
(f) smaller
(g) current
(h) brighter

2. Ammeter, rheostat and fuse p.90
(a) rheostat
(b) resistance
(g) (electric) current
(h) black
(i) positive

Workbook Answers Ch7 Integrated Exercise

Integrated Exercise
A. Concept checking p.30
1. True
2. True
3. False
4. True
5. True
6. False
7. True
8. False

B. Multiple choice p.30-34
1. C
2. C
3. D
4. D
5. D
6. A
7. C
8. D
9. C
10. B

C. Matching p.35
1. (a) ii, iii, v, vii
(b) i, iv, vi, viii

2. (a) iii, iv
(b) ii, v
(c) i, vi


D. Questions p.36-41

1. (a) (i) oxygen
(ii) Put a glowing splint into the test tube. If it relights, it shows that the gas is oxygen.
(iii) It is used to provide carbon dioxide for the water plant to carry out photosynthesis.

(b) (i) The rate of bubbling increase.
(ii) The rate of photosynthesis increases when the light intensity increases.

2. (a) (i) It remains colourless. It shows that no carbon dioxide is present in the air entering the bell jar.
(ii) It changes from red to yellow. It shows that the mouse releases carbon dioxide.

(b) Sodium hydroxide solution absorbs carbon dioxide from the incoming air. This ensures that the colour change of the indicator in flask C is due to carbon dioxide released from the mouse.

(c) (i) Place the set-up in the dark. (or other reasonable answers)
(ii) Without light, the plant cannot undergo photosynthesis. This ensures that the experimental result is due to respiration of the plant only. (or other reasonable answer)

3. (a) (i) Respiration: food + oxygen ==> carbon dioxide + water energy
(ii) light energy
Photosynthesis: carbon dioxide +water ==========> food +oxygen
chlorophyll
(b) (i) The rate of net oxygen absorption will be negative.
(ii) The rate of net oxygen absorption will be positive.

(c) (i) From 0600 to 1800
(ii) From 1800 to 2400 and 0000 to 0600

E 4. (a) (i) B to C, D to E
(ii) N to P, R to T

(b) The chest volume decreases while the gas pressure inside the chest increases.

(c) (i) The intercostal muscles relax, causing the ribs move downwards and inwards. Hence, the volume inside the chest decreases.
(ii) The diagram moves upwards, thus the volume inside the chest decreases.

Workbook Answers 7.6

Section 7.6
A. Multiple choice p.23-24
E 1. D
E 2. D
E 3. D
E 4. C

B. Fill in the blanks p.25
E (a) contract
(b) upwards
(c) outwards
(d) downwards
(e) increases
(f) decreases
(g) relax
(h) inwards
(i) downwards
(j) upwards
(k) decreases
(l) increases

C. Matching p.25
E (a) v
(b) i
(c) ii
(d) vi
(e) iii
(f) iv

Workbook Answers 7.5

A

1.     B

2.     C

3.     C

4.     D

5.     C

B

(a)

Tube	Does respiration take place? (ü / û)	Does photosynthesis take place? (ü / û)	Colour of the indicator	The level of carbon dioxide (unchanged / increase / decrease)
A	ü	ü	red	unchanged
B	ü	ü	purple	decrease
C	û	û	red	unchanged
D	ü	û	yellow	increase
E	ü	û	yellow	increase
F	ü	û	yellow	increase
G	û	û	red	unchanged
H	ü	û	yellow	increase

(b)    In the dark, the plant does not undergo photosynthesis. However, both the plant and snail carry out respiration which gives out carbon dioxide. Therefore, the level of carbon dioxide increases and the indicator changes from red to yellow.

(c)    Under bright light, there is a net intake of carbon dioxide in plants. In the dark, there is a net release of carbon dioxide in plants.

Workbook Answers 7.4

A

1.     False

2.     False

3.     False

4.     True

5.     False

B

1.     A

2.     D

3.     D

4.     B

5.     D

   6.     C

   7.     A

8.     B

C

1.     (a)    carbon dioxide

(b)    water

(c)    food

(d)   oxygen

(e)    starch

   2.     (a)    feeding

(b)    photosynthesis

(c)    producers

(d)   green plants

        (e)    consumers

D

1.     (a)    A:    II

B:    IV

C:    I

D:    III

        (b)    C → D → B → A

        (c)    Dark blue

        (d)   This leaf has carried out photosynthesis.

   2.     (a)    Chlorophyll

        (b)    (i)     Presence of starch in the leaf

(ii)    1.     Destarch a potted plant with variegated leaves by putting it in the dark for 1 or 2 days.

2.       Put the potted plant under bright light for an hour.

                        3.     Remove a variegated leaf from the plant and carry out the iodine test on it.

                (iii)   The green part becomes dark blue; The non-green part remains as brown        

                       

        (c)    Chlorophyll is necessary for photosynthesis.

   3.     (a)   

Producer	Consumer (feed on plants directly)	Consumer (feed on plants directly)
Grass, trees (or other reasonable answers)	rabbit, zebra, grasshopper, bird (any two)	lion, snake (or other reasonable answer)

        (b)    (i)                     eaten by                           eaten by

---->
        grass                               zebra        ----------->                        lion

                (ii)                    eaten by                           eaten by

        grass          ------>            rabbit       ------------>                       snake

        (or other reasonable answers)

        (c)    (i)     Light energy

(ii)    chemical energy

                (iii)   chemical energy in animals

Workbook Answers 7.3

A

1.     True

2.     False

3.     True

4.     False

5.     False

B

1.     (a)    chemical

        (b)    respiration

        (c)    living cells

        (d)   oxygen

        (e)    carbon dioxide

        (f)    water

2.     energy content

C

1.     (a)    (i)     A: oxygen; B: water / carbon dioxide; C: carbon dioxide / water

                (ii)    Support body functions / support movement / maintain body temperature.

(any two or other reasonable answers)

        (b)    (i)     X: oxygen; Y: water / carbon dioxide; Z: carbon dioxide / water

(ii)    In both respiration and burning, oxygen is consumed and carbon dioxide and water are produced.

        (c)    Respiration occurs in living cells while burning takes place in air. /

A flame exists in burning but not in respiration. /

Respiration is a much more complicated process than burning. /

The energy is released much slower in respiration than burning.

(any two or other reasonable answer)

2.     (a)    Increase in temperature per gram of food

(b)    60℃

        (c)    The highest water temperature reached  =    Water temperature at the beginning +

                                                                                      (change in water temperature for 4g of

                                                                                      food Z used / 2)

                                                                                =    20℃ + 60℃ / 2

                                                                             =    50℃

(d)       Food Z

(e)        Food Y

                  Overweight / coronary heart disease / diabetes (any two or other reasonable answers)