F2 IS 2nd Term WS05 10.1 Answers

2nd Term WS 05 Submission date：_____________ Name：______________________ Class & no.：2 _________(     )

10.1    Acids and alkalis in daily life

i      Words to know:

	English term	Write the words again	Chinese term
1	Acid		酸
2	Sour		酸味的
3	Lactic acid		乳酸
4	Citric acid		檸檬酸
5	Ethanoic acid		乙酸
6	Hydrochloric acid		氫氯酸
7	Carbonic acid		碳酸
8	Alkali		鹼
9	Bitter		苦味
10	Soapy		似肥皂的
11	Slippery		滑溜的
12	Ammonia		氨
13	Sodium hydroxide		氫氧化鈉
14	Potassium hydroxide		氫氧化鉀

i      Fill in the blanks:

1      In our daily life, there are many foods, drinks and flavourings that taste sour. It is because they contain

         acid. For example,

n   Yoghurt contains lactic acid.

n   Lemons contain citric acid.

n   Vinegar contains ethanoic acid.

2      Many household cleaners and personal care products also contain acids. For example,

n   Toilet bowl cleaners contain hydrochloric acid.

3       Alkalis are the chemical opposite of acids. They generally taste bitter, and feel soapy and slippery.

4       Besides soap, some household cleaners contain alkalis. For example,

n   Glass cleaners contain ammonia.

n   Drain and oven cleaners contain sodium hydroxide or potassium hydroxide.

i      Everyday Science:

1.       Fizzy soft drinks contain carbonic acid which is formed by dissolving carbon dioxide in water.

2.       The gastric juice (胃液) in our stomach (胃) contains hydrochloric acid.

Ch 9 Workbook Answers

F2 IS 2nd Term WS04 9.4B Answers

2nd Term WS 04 Submission date：_____________ Name：______________________ Class & no.：2 _________(     )

9.4 B    Action and reaction (P.28-32)

i     Words to know:

	English term	Write the words again	Chinese term
1	Action-reaction pair		作用力和反作用力
2	Equal		相同
3	Opposite		相反
4	Eject		噴射
5	Launch		發射
6	Overcome		克服

i     Fill in the blanks:

1      When an object exerts a force on another object, it experiences an equal force in the

         opposite direction at the same time. These two forces are called an      action-reaction pair.

2      During a rocket launch, a large amount of hot gas is ejected downwards

from the rocket. The ejected gas produces an equal force that pushes the rocket upwards.

The great pushing force overcome the force of gravity acting on the rocket.

3       During a water rocket launch, the water is ejected downwards from the rocket. The ejected

         water produces an equal force that pushes the water rocket upwards.

i     Multiple choice: Circle the letter of the best answer for each question.

1.      When an inflated balloon is released, it will fly away. We can explain this in terms of

A. Friction                B. action and reaction               C. weightlessness                     D. gravity

2.       What forces does a rocket have to overcome when it is launched from Earth?

(I)                 Force of gravity

(II)               The pushing force due to the hot gas coming out from the rocket engine

(III)             Air resistance

A. (I) only                  B. (III) only                   C. (I) and (II) only                 D. (I) and (III) only

F2 IS 2nd Term QZ 02: 9.2 anwers

2nd Term QZ 02 Submission date：_____________ Name：______________________ Class & no.：2 _________(     )

9.2

Word Translation (9 marks)

i    Write down the English terms of the following Chinese terms:

	Chinese term	English term
1	空氣 (或水) 的阻力	Air (water) resistance
2	氣墊	Air cushion
3	滾珠軸承	Ball bearings
4	摩擦力	Friction
5	潤滑劑	Lubricant
6	相反 / 對抗	Oppose
7	滾子	Rollers
8	滑動	Sliding
9	流線型	Streamlined shape