1970-04-08 — Page 26

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星:安八月四年八七九一座公气力十五屆民范中育教你對

probable

A. ethylene

B. acetic aciu

C. methanol

D. ethane

B. acetylent

中學入學試試題預習專欄

英文科

赞出版社主編

(1=)

sodium nitrate

B. ammonium nitrate

C. lead nitrate

D. potassium chlorate

E. hydrogen peroxide

of a gaseous mixture contains 5 ml.

Anevere to Previous

Exercices

1770英文中學會考試題預習專欄

9. The following compounds yield a common gas

on heating except:

SECTION

I:

2.B 3.0 4.E 5.B:

SECTION BII

eren't you

A

書院主編

are you

wasn't be

we aren't

he isn't

化學利

(1=)

10, 15 ml.

CHEMISTRY (23)

wayn't it

they had

be does

it can't.

1. John asked. David if he could

2.

My

there that night.

sister said, "The exercise is difficult."

3. Tone father asked him whore no

had been all day.

Dick said to me, I found the

secret yesterday."

The policeman ordered the man

to stop.

QUESTIONS

1. In which of the following compounds are

covalent bonds present?

I ammonium chloride

II. sodium sulphate

I sodium chloride

IV. chlorine

V. hydrogen chloride

Which of the following alternatives da

correct?

A. I, II, II only

B. IV only

C. V only

D. IV and V only.

B. I, II, IV

th Organ to balance the above equation,

In

figures should be in the order:

221222

-B. 222244

0. 211222

D. 111122

E. 111112

The volume or 0.7N HCl that should be addźd to 200 ml. of 0.2N H280 to make the resul

ing solution 0.5 is

A. as the two acids are different, no

calculation is possible

B. 100 ml. of 0.7N HC1

C. 3/7 x 100 ml. x 2 of 0.7N HOL

D. 300 ml. pf 0.7N HO1

E 400 ml. of 0.7N HOL

A 2.25 gm. sample of an acid having an

equivalent weight of 75 was titrated with standard base. It was found that the percentage purity was exactly 100 times the normality of the base. What volume of the base was used in the titration?

A. 3.3 11tres

B. 33.3 ml.

C. no solution possibl

D. 30 ml.

E. 3 litres

Element I has an atomic number 19. Using knowledge of the periodic table, predict the most probable compound that it will forn with element of atomic number 17.

9. II

D. Y:XY

5 ml, methane and 5 ml. carbon monoxide. The mixture has a vapour density of: A. 2.6

B. 5.2 0.7.67

D. 13.0

E. 15.34:

SOLUTIONS

1. 6 (I, II, IV, V only

Chlorine and hydrogen chlorido are covalent compounds. Although ammonium chloride and sodium sulphate are fonie compcunda, never- theless there is the presence of covalent bonds in the radicale ammonium and sulphate.

2. D (111122)

This is an example of oxidation-reduction reaction which can be interpreted as an electron transfer process. To balance the equation, one may consider the change in oxidation number of the oxidant and reductanı

So to SO, O.N. of S: +4 to 1ồ

Er to Br 0.N. of Br: 0 to -1

Thus to complete the electron transzer process 1g ion of So, reacts with 1 gm. molecule of Br2 to yield 1 gm. don 50

and

2 ga on Br. Tha equation te then completed

by adjusting the amount of H20 and H

either eide to maintain conservation of mass and ele#trical neutrality.

D (300 ml.)

0.7 x V + 0.2 x 200 = 0.5 x (V +200)

where V is the volume et 0.7M HOL to be added. 7 - (0.5 -0.2) x 200

0.7 -0.5)

300

D. (30 ml.)

Let % purity = X Thus normality of bass m

2.25 100

75

where T is the volume of base used in litres. thus V30 1.

The electronië

10 2.8.8.1

SECTION

(multiple choice)

Read the following letter carefully)

Dear Hexy,

24, Ice House Street, 5th floor, Hong Kong.

25th February,

It is my birthdey on Saturday and I am linvtri, a party I hope that you will be able to come. Try to arrive at our house at about four o'clock and tell your parents not to wait for you home before half-scst

eight.

One of the presents. I shall be receiving is a toy camera and my cousin Brera has picmised to bring several of her films along. We should have a good show.

hope that your parents are both well.

Your sincere friend,

Barbara,

Now choose the right answer by drawing a firm line

across the correct box.

The letter wes

A Father.

B. Mother.

C. Barbara.

D. Brenda. B. Hary

ABCDE

ABCDE

00000

A Cousin B. niece.

Mary was Barbara's C. sister.

D. friend.

E. mother.

{A, Barbara's B. Brenda's

A B C D E

D. your

conriguration of I of At. Io. 19

E her parent

birthday party,

A. a friend B. a house

AB.C.DE

y was invited to C.my.

E. XX

[6. ne following are characteristics of a

catalyst:

I. it remamy ynysically and chemically unchanged during a chemical reaction II. it may accelerate or retard the rate

of a chemical reaction

II. it máy be dispersed homogeneously or

heterogeneously with the reactants

IV. it is able to initiate certain reactions

that do not normally occur

it functions by shifting the equilibrium position of reversible reactions

Which of the following alternatives is correct?

A. I, II only

B. I, I only

D. I, II, I only

That of Y OF AV

BO 17 18 2.8.7

To complete a stable cotet, I must receive an extra electron.

To attain a stable octet, I may loss 1 electrons Thug a compound between I and I can be formed

wielding IY

by Alantean, dramata

62 C (I, III only)

catalyst often undergüen a pHYSLERI Cnange of state during a chemical reaction.

A catalyst cannot initiate chemical reactions.

A catalyst leaves the equilibrium of reversible reactions undisturbed.

The girls would have C. a toy camera

D. a present. E.a film show

at the part

A. London

B. Macao.

5. Barbara lived in C. Kowloon.

D.. Hong Kong. E, Banton.

A B C D E

II. Choose the right word which best brings out the

meaning of the sentence. Draw a firm line across the correct box.

If you have tooth eohe, you should go

P. evelist

2. chemist,

see the R. dentist.

S. florist.

T. artist.

PQRS

C. II, II only

E. I, II, III, IV,

A molar solution of a solute dissolving in

water contains:

A. one gram-equivalent of a solute in 1 litre

of water

one gram-equivalent of a solute in 1 litre of solution

one gram-molecule of a solute in 1 litre

of water

D. one gram-molecule of a solute in 1 litre

of solution

one gran-molecule of solute in 1000 gm. of water

An unknown organic compound decolorises readily acid potassium permanganate solution but not bromine water. The compound is

Alcohols (except tertiary alcohols) are oxidizable by acid permanganate solutions, but they do not react readily with bremina water.

All yield oxygen except ammonium nitrate which yields nitraus oxide.

10.0

T.D. of

2 V.D. of CH Y.D. of CO = V.D. of

12

16

mix

NEXT WEEK

7.67

More exercises in multiple choice objective teats

farmer

Q barber

2. AR. barker

FORST

gets his living by

S. butcher

T.

people's hair.

are one hundred years in:

P. country.

Q. grocery

R. factory.

S. century.

Tlavatory

PQRS