1970-04-16 — Page 23

KLFERNGE LIBRARI

16.

育教俊華:

百三十二月三年戌庚展夏 WAH KIU YAT PO

報日僑華

四門星 日六十月四年〇七九一公年九十五國民華中

ERO英文中學會考試題預習專欄

中學入學試試題預習專欄

ANSWERS TO PREVIOUS KIERCISES

·海道英文書院主編

化學科

(十四):

英文科

智慧出版社主編

(廿四)

SECTION

II

1.0 2.D 3.A

1R 2.9 3.3.

4.B

5.D

5.P

CHEMISTRY (24)

QUESTIONS

The following reactions are all affected by Lign

xcept r

Combination between chlorine and hydrogen B. Combination between chlorine and methane C. Combination between chlorine and ethylene.

Combination between water and carbon dioxide in. green leaves

E. The darkening of silver chloride

Cheap grades of common salt get wet when exposed to air for some time,

because

A. Sodium chloride is deliquescen

9. Sodium chloride in efflorescen

G. Contains sodium hydroxide as an impurity

D. Contains salcium chloride as an impurity

B. Contains magnesium chloride as an impurity

If methyl alcohol is allowed to react with acidified potassium permanganate, it will be oxidized tor

A. Formaldehyde

B. Formic aold

CCarbon monoxide

D. Carbon dioxide

3. It is not readily oxidized under the given

condition

Which of the following compounds in aqueous: solution will turn red litmus blus”

I. Sodium hydroxide II. Sodium nitrate

III. Sodium acetate

IV. Sodium carbonate

V. Sodium bisulphate

Which of the following alternatives is correct?

I only

I, III, IV only

I, IV only

9. 1. V only 5. II

Vonis

After the accident, the injured driver was taken P. stable. 2. kennel.

PORST

nospital in an R. garage.

S. prison.

Tavator

person who walks on a road is called

Fmotorist.

2. passenger,

1. pedestri an

S. traveller:

T. qvelist..

SECTION

II. Read the following carefully:

One morning a gectionor was watering the florer-bada in a garden. At midday, he turned the tap off and went to sit in the shade of a tree to eat his lunch and have a rest.. A small boy and girl ran up when they saw him turn the tap off, and looked first et the tap and then at the gardener, When they saw that he had gone to sleep, the girl turned the tap on and meat the boy with the water from the hose-pipe. Then she began to wator a flower-bed. While she was doing this, the boy quietly turned the tap off. The girl did not know why the water had stopped so she looked into the hose-pipo

to sea what bed kappened. While she was doing this, the boy: turned the tap on again, and the girl got wat. She was zo surprised that she turned the boss-pipa stay from herself suddenly and wot the garians, she awoke with a big jump.

fera are ton statements about the passage.. Some of the are tuo and some of them are untrue. Put a tick (E against the ones that are true and a cross ( cgainst those that are untrue,

The story took place in- a big garden.

SECTION B: III 1. The game has been finished by them.

The news was told him by his friend.

IV

(or: He was told the news by his friend)

3. It was done by you yesterday.

4. They elected her "Kiss Hong Kong.

5. When will they set the man free?

DICK How are you going to spend the

svening, Sam?

SAM: Oh! to the cinema, perhaps.

I've done all my work. Have you done yours, Dick?

DICK: Yes, all that I am going to do.

then? SAN : Can you come with me,

DICK : Certainly! I am always ready to go

to the picturea.

SECTION (multiple choic

Choose the best answer and draw a firm line across the

right box.

A. is swimming. B. was swimming-

1 While Peter C. swims.

D, swam

E. will swin

sea, a jelly fish stung him.

A playeu... B play

Up to now we C

games,

are playing have played

E had slavað

in the

A B C D E

A. are crossing B. will croFS

A B C D E

D. crossed E. have ero3304.

Look carefully before you E. cross.

The gardener had turned off the tap before heơ

went to have lunch.

There were a lot of people di the garden.

3.

The gardener took a rest after lunch

If you are provided with three chemicals cono. sulphuric acid, potassium nitrate and ammonium chloride. Which of the following gases could you not prepare?:

4

The gardener was working hard when the chilärsä

played with the hose pipe.

A Nitrous oxide

B. Nitrogen diori..

C. Hydrogen chloride

D. Ammonia

E. Oxygen

8.

When a mixture of conc. sulphuric acid and solid. potassium bromide is heateds

A. Only pure

A. Only pure bromine 18 formed

B. Only hydrogen bromide is formea

C. A mixture of bromine and hydrogen bromide

formed

A mixture or bromine and sulphur dioxide in formed MTAA WA

EVA mixture of bromine, hydrogen bromide and

sulphur dioxide is formed

7. Which of the following substances can dissolve

readily in dilute hydrochloric acid?"

Only two children and the garconer wore in the

garden.

The gardener started watering the flowers at

midday.

The girl was surprised because water zuddenl

came out from the pipe.

The gardener jumped up from sleep bECRUSO

girl watered him.

All the taree persons et wat in the garden.

0000 0000 00

the road.

A. with B. at

A B C D E

Do you like sugar and milk G. for

D. of

5. beside

A. et B to

ABCDE.

Hurry

and make C. of yo

Don

mind.

One word in each line below does not rhyme with the

word written in capital letters. Put it in the margin on the right.

chock rot smoke boot look sno

tood quite near but still I could

P. 11sten

he ar

notice

them talk clearly.

-300

FOR ST

DOODD

1. Zino sulphide

IT. Lead chloride

TII, Barium sulphati

IV. Silver nitrate

V. copper sulphide

Which of the following alternatives is correct?

A. I, II only

B. I only

CI, V only

D. I, IV only

E. II, III, IV only

8. If 1.68 gm of a metal B is obtained through

reduction of 2.32 gm. of its oxide, given that the atoma weight or K is 56, the most probabli formula of the oxide is

A 20

3. MO

MO;

Exam

Hook

feel

COW

6. BLUE

7. DOOR

allow

SPADE: made lake

DEAR: clear 3pee

DARK walk

SPIT hit beat

do

drew

blow now

Jade paid stayed 2.

cheer heir fear

such

ay

car is not R. so

iseful as

P Q R S T

S much

rathet

split sat

blew

lit

boat to a fisherman.

ΠΟΤΕ

pour

choir

through

vär

8. FEEL

fil

SEW

CAME

§ to al

snow

amė:

eel

ohew go

stamp tame

steel 8.

flow 9.

When Mr. Lam does not go out he usually

keeps his car the Re garage.

P. stable.

kenne

PQRST

1'lare

prison. lavator

E

9. If a current of 4 amperes 18 passed through an

alectrolyte for two-thirds of an hour, and given that one Faraday is 96,000 coulomba, what is the volume of oxygen that will be liberated at NTP conditions?

A. 22.4 litres

B. 2,240.0.0.

C. 5.6 litras

D. 560 ml.

E. 280 ..

10. A white powder X 18BOLVES 10 water to produce blue Bolution. After acidification with dilute hydrochloric acid, barium chloride is added and a white precipitate appears. What will happen: if lead nitrate solution is added to an aqueoua solution of X?

A. No observable action

B. Evolution of a brown gas

The combination or onierine with ethylene is "ani addition reaction that need not be catalysed by light.

Magnesium chloride occurs as an impurity in common salt prepared from sea water, it is deliquescent substance.

Methyl alcohol 18 oxidized by @trong oxidizing agents to carbon dioxide and water

B (I, III, IV)

In addition to sodium hydroxide, solutions of sodium acetate and sodium carbonate are alkaline. This is because they are sodium salts of weak acids, partially hydrolyzed in water.

exceps ammonia, all other gases can be prepared b suitable combination of the chemicals

G. White precipitate insoluble in hot water

D

D. White precipitate soluble in hot water

E. Disappearance of the blue colour of the

original solution,

SOLUTIONS

As nyarogen promine is a reducing agent, it a readily oxidised by sulphuric acid to bromine, tho acid being reduced to sulphur dioxide.

7. B (I only)

Only zino sulphide is soluble in dilute hydrochloric acid. Although silver nitrate is noluble in water, it yields the insoluble silv chloride when in contact with hydrochloric acid.

1.68 gm. M combines with (2.32 - 1.68) - 0.64 en oxygen

1.e. 3 ± 56 (M) with 4 x 16 (0) thus formula1 M_0,

D

Gram-molecular нt.

Gran-molecular volume at NTF - 22.4 litres Since 1 gm, equivalent of oxygen 8 an Thue volume occupied. by 1 gm. equivalent of oxyge. at NTP (22.45) litres = 5.6 litres Quantity of electricity passed

-

(4x40xous courofius.

9,600 coulombe 071 Faraday

As 1 Faraday of electricity liberates gn- equivalent of oxygen, 0.1 Faraday would liberg si 0.56 litre of oxygen at NTP (560 m2;)

C

Barium eulphate is precipitated in the first reaction. Thus when lead nitrate solution 19 added, lead sulphate will be precipitated,