bs the cost of
month (30 days).
=SA+3.5A
- 8.5A
日四十月三年八八九一曆公年七十七國民華中
dioxide and hydrogen eulphide.
二國民華中
頁四第張五第 日七廿月正年辰戊夏
WAH KIU YAT PO
報日僑華
一期星
from the asins
o marked on A.
electricity for one
any other gaseous alkere), sulphur
1988中學會考 試題預習專欄
(*) (1)
Resistance of 1
H
Examples
system as shown in
物理(廿四)
·第一級鋼琴獨奏冠工陳允昕捉到海打氣的父母合抵。
第四十屆校際音樂節特輯
十一依以下男女合唱協和下午校老師及代表按受記者訪問。
初級組1ē季必冠谁义叔街(右)與老師合照。
小學組聖詩合唱;青衣商會學校代表箫棉,
明洫出版社
(b) If now a heating unit (200V,70UM) in added La the kitchen by
connecting in parallel
with the lighting
unit and cooling
the figure below.
6 A fuse box
MILL & DALE PRESS
lighting
nuit
Revision Exercises
for
Cert.Exam.(1938)
PHYSICS (44)
Domestic electricity.
Mains cable contains
3 vires; a live, a neupral
and Au earth wire. The
colour code for the se
wires are brown for live
(L), blue for neutral (1)
and yellow and green for earth (E).
Por household appliance, the north wire should be connected to the ense
(metal case) and the live vire should be coanented to the ON-OFF svitek. The following diagram shows how a household appliance.
ia connected.
socket
nit
Example:
(a) as shown in the figure,
a electric circuit for
a kitchen consists of
lighting
(2004, 2014) ond a
cooling system for
e refrigirater (200V,
SW).
GA
fase
box
lighting
200 V
cooling.
system
{i} Find the saximum
current drawn from the mains,
(ii) If u 6A fuse is used
in the fuse box,
will the fuse blow?
(ii1)If electricity cost
60 per kWh and the
whole kitchen is in
full'une for 10 hourB everyday. What will
欣欣
cooling
aystem
hoating
unit
switch
What happens, if all appliances are switched-
on. Explain briefly.
Solution:
(i) Using P = TV
导
Current through
light whit
house hold appliance
heater
Which is much larger
thon 6A and thus the
理性的就是II blow.
(a) A lamp A marked "64,
12" in commented in series with a 10 resistor and a by
battery. Assume the internal resistènce
of the buttery and the resistance of wire are negligible.
fil
Find (i) the current
through lamp A.
(11) the pover
dissipated
(iii)explain.
briefly why the power
ried
on the lamp.
(b) If lamp B, marked by
12V, 12W is inserted
ON-OFF Bwitch
200
LA
(三)
Current tha
cooling synteti«'
800
A
-200
xing current
(11) No, for the maximum
current is smaller than GA.
(ii)Energy consumed each
day
= (5)(200)x(10) Wh.
Ferry CoBsumed ench
9.30
300 AWA
at for the month
=(0)x0,6
(A) (b) If the heating unit is
switched on, gurrent through heating
unit is given by
放上请典有限公司 3-852277 3-849792 3-841331 BAY NI SWING 1350238
700
台北四天花薄膩$2340 台北酒店、特價酬賓
175:193
resistor and lamp A as shown in figure below.
你
brighter? Why? i) I now lamp A is
taken away, would lang brighter
part (a) Why? Solution:
(á)
(1) Resistance of A
A
- 30
Current through lamp
ts
Z
(Ana)
(ii) Power dissipated by A
(1.5)*(3)
•.0.75 K
(iii)P.d. across lamp A
(Ans.)
= (1.5)(3)
= 4.5V
Since the voltage
scross lamp A is less
3-969861
世
12450
connected in series. Power dissipated in
Power dissipated in B
A
319
1 上
..B will be brighter. (1) Lamp D will be
brighter than that nt Jump A in part (a), it is because resistance of 8 compared with the
1 resistor is oue) higher than that
of resistance of A compared with the 12 resistor. Thus the energy ia因为
dissipated in the In redistor is ameller than that in part (a).
化學(廿四)
MILL & DALE PRESS
Revision Exercises for Cert,Exam. (1988)
CHEMISTRY (24)
Ajuestions延
The mua paper
remain
unchaded.
(ii) It is because the
solution X does not consist of any
mobile ions ds BCI still exista as covalent molecules, (ii)White precipitate of
wwmonium chloride would be seen. This ie because ammonium chloride, being ionic in nature, does not dissolve in methyl beazone which is covalent (iv) The electronic
ammonium chloride is as shown below.
Key: electrons of
nitrogen
康樂
electrons of chlorine
electrons f hydrogen
They are ethene (or
5-441531 牌照海碩350440
(ii) Gne X is expected to
be sulphur dioxide. (iii)The equation is:
BaCly+30+H→
BagQiy(s)+2in1 (c)Moes of 720 cm of
solid residue) -2.45-1.49
0.96 £
"mass of 1 mol of gas 2
4000 0.96x-720
~38
H(Z) is 32. Answer to Questions 35
(i) As read from the
grup X and Y have the same salability
at 90°c and the value je 50 g.
70°C and 9 p at 50°C respectively.
(111)At 70°c, 100 g of
water dissolves 27 g of Y to form 127 g
of a saturated Bolution.
But, at 30°, 100 g
of water only
disaelves 9 g of v.
Thus, when 127 g of saturated solucion
er Y at 70°C is eobled tu 30°°C, (27-9)=19 g of
crystals of Y would be formed.
Bess of Y that would be obtained on`evoting 50 g of solution saturated of Y AL 70°C
30°C
Lo
327
Mass of
-(120-45) $75
40°
maximum
X that dissolved in
of
75 g of water at 40°C
28.46
mues of X deposited =(45-28.5)
-16.5 g
(v) At 40°C, the
solubility of Xia 38 g and that of Y la 38.g.
maximus mess of X that dissolves in
50g of water at 40°C
.19.
50
and, maximum nasa of.
X that dissolvgë
50 g of wate
50
sb R
the mixture orginally
conlaius 15 g of X
and 15 g of Y.
1 X is dissolved but (13-6)=0 of Y remains undissolved,
(1) X is prepan-1-el. (11 cannot be
(b)
nu axidization, it would give
instead of
'ketune
alkanoic acid).
Bis propanoic acid. Cin.1-chlorotropane. Din propyl
ethanoate,
(1) Conc. Hg804.ia used
and beut has to be upplvet.
CII CH CH2OH---
CHgCH=CHy+E20
(2) Acidified potassium
dichromate for potassium permanganate) is used and heat has to be applied. CHgCNQCHOH+2(0)
(3) Phosphorua{V)
chloride (or phosphorua(11) chloride) is used und the reaction would take place at
room temperature,
CW, CH, CHUL+PC45
--- CH, COUCH.CH.CRT
(1) I is the addition polymerization.
(2) Y is pulypropene.
CH3CH-CN2.
C53 H
Answer to questions 36
Nerggen is obtained FromBair by fretional
distillation of
liquid air. Rydrogen is obtained from
water by electrolysis of acidulated water. (11) The yield of NH-
t be incressed Ausysing slow
temperature. Since the forward reaction exothermic 90, Jov temperature 11 shift the quilibrium position to the right.
(ii)The yield of NH2
is favoured by using a high pressure. Since
the number of moles
of ganeous reactanta
is greater than that
of the gaseous
PATA
育敎僑華
product, so a high
pressure will whift
the equilibrium - position to the right.
(iv) According to the
equation
Jaol mel
Imol mol
amount of Nil
=21
!
The ammonia can be separated from the mixture by
1
dissolving it in water for directly in a dilute acid for making the
fertilizers)
(2) They are dried and
used again.
(vi) A suitable, catalyst
is iron powder, (vii) of nitrogen in
(NE)930年
(b) (i)
2x14
-21.21
14
of nitrogen is
-10.47
Thus, acgeniun
sulphate is the
cheuper source
A is sodium bromide.
9 is hydrogen
bromide.
Cie iron(1)
bromide, (anhydrous)
D is hydrogen gas. (ii)Concentrated
sulphuric acid is
used.
NaBr+H,50 Nah30, tr
(iii)Sodium chloride is.
alau formed,
Cl2+2Br --> 201 ̄ +Bra
(iv) The flame is pale
blue in colour
{v) At the anode
chlorine gea is liberated
→Clg+2e-
At the cathode bydrogen gas is liberated
(vi) Bromine atom has 7
electrons in the outermont gbell, aw. _che bromine molecule
has the following electronic structure.
。
(vii)Chlorine has a
utronger oxidizine power because it has
stronger utfinity
for electron than
bromine.
捷威旅行社 ¥
MEMBER OF PACIFIC: CONCORD GROUP 14P MLEVEN U
than GV, therefore
200
the power dissipated
(Total.current da
is not equal to 12%
寶通旅運
3-910377
台灣渡假團 四天$800 天天出發
台灣豪華團 特廉機 七天 $3090
的
清邁豪華團 四天$ 2560 逢週三、六出發
逢週日出發 韓國豪華團 四天單人房 天天出發
九龍旺角彌敦道635號銀行中心2110室
台灣急譲$150票證130牌號碼:350720 ̇台北機票+酒店三晚$1470 天天出發
旺角彌敦道六五五號胡社生行7412室
❤
三藩市$2000 A 浩杉雞$2000 西雅圖$2000 夏威夷 $ 1600 年
越 約$238G 溫崭蕺$2400 門原$2880 多满笋$3300
·温尼泊$3500 南斃$4506
歡迎{VISA卡沙款
光,學生物 纲:數$2200 歟洲$2350 A 台北$:770 東京$ 850 韓國$1650 星加城 $1080 啡·尼$2250 曼谷$730 配尼拉$1200 澳洲$2800
北
七天豪華團
天天出發 保證住構職都假日酒店。
七天高极航空围 天天出發
$2390|桂
星 承德七天航空
天天出發
台北溪鎮五天團 $2590- 阿里山六天團 $2890 東京豬士尼五天團 $4690 軽城游州四天E $3390 泰國芭堤雅五天團 $2590
泰國布吉島八突團 $3590 繻燃爲塋六茨團 $4080
新航嚮星泰九天團 $5199
安:150
H438456
新華旅行社|菲航美洲假期 常運旅行社有限公司 4450568
歐洲 歐洲五國10天紹使團 $ 8,330
歐洲七國12天豪華團 $ 9,580 歐洲七國13天精選團 $10,280 「逢星期六出發 歐洲八國16天精選團 $12,380
-女佈臂猴唱冠軍梁思緻,亞 陳淑慧 A
直會林兒與钊評黃水揉合照。
·二重唱絰軍得主蘺称典宮陳瑞同學铵獎
露出務利的美容
萬名雅。
馬
牌照:35Q1650 夏威夷美國西岸 七天
·夏威夷美國西岸八天
·夏威夷、籐省賭城九天 美國東岸奧蘭度十一天 美國加拿大東烨十三天
$ 6998 $7788
$ 8080
$13288
$14688
熱線電話:3-7232882,3-7230399
成都至各地機類(四川省中旅社取襄 廣州600 拉廣 800 實簿 350 武漢 480 昆明330 西安 330 火源 440 長沙 430 北京 560 南京 550 重慶 260 藺 480 ## 430 上海 600 西昌 200 沈阱 680 成都至各地火${軟臥)(四川省中旅社取骠) 280 昆明320 北京430 廣州500 太原410 重慶 西安310 實暢320 上海500 武路410 重慶(款)210
LASER (1) 329 (m450 (2490 悅票酒店$30 花園酒店430 中國大酒店500 代訂全國各地或破鏝弊台術、逖儒一外建特快粉
大門 旅遊有限公司 | 大大関
台灣旅客回鄉
探親喜訊!!
吉隆坡、能丹、馬六新加暗社家還拔期四 $4350
雪藏,登堡、馬六甲,新加坡七天 *-* $4356 丹 今船素東西岸、丹、擋枝)八天 逢星期四 34640 監鴦要檳城、荔六) 布省島十二天 逢星期五·日$5000
丁藏校,馬六甲,新加城·布吉島、攀牙灣,然埕罪,曼谷
*肃櫞庹葺欈能住宿费高級之身為里拉大酒店·新加坡性
宿屭来登大酒店
350013
(廉價代訂)
ATINAS ATEX RADZIN STEVE AO Na
16
牌照號碼:350338
五天廈豪華團二、五出發 $1.790
$2490 海南島六大高极桥空量 天天生發 $1590
五天匯航豪華團天天出發$1590 五天高級航空露天天出發 $1290
$2390 | 林 南寧、柳州、桂林七天航空里 $1650
運二、四、日出發
辦公時間朝尢漁上
·遇台只假照常辦公|
想动:銅鐵灣軒尼詩≥555號黨為中心19字(崇光百貨樓上) 05-8336667
5-212527, 5-254596 ZEAT3-72001E, 3-7809313 0-4988447
经夠保险有限公司锁状态 Coolingvit Scang *看欧心,
錦江限城信心擔保 Conn-Travel Scheme 儺我莒調 盩𥴊传人
5-765651 5-8600623 = 356154
哦主 PA 1934 CMMAKER ER SEMANA 1 Allyn
*香港直航中國各地機票。 *香港至廣州各項交通 *廣州至中國各地機票 *中國各地酒店訂房
$27401
到超
減!地莪逢星陀二
五天/他還黑期五
六八式餐期過日
鴉,桂河檔,清邐,非有一樂牙潔,拉軍濕、刪 練,它物圖全國躍景名和
永安旅行團
11490
̇ ̇尼拉 百瀾五灭
·豬滿翼,熊尼拉·翻七
3-8
}
iP
望
::
说来
Again to the
CARRY ON INAVEL 旅運有限公司
佳麗安
註冊牌照號碼:350348
5-254549.41 5-241845
夏威夷美加$4490起,歐洲十天 $9183
日本
$4690起 菲律賓 $1890$0
$4099起 泰國
星 國
$3340起 台灣
$ 2520已
$25903
印尼九天 $5699起 澳洲七天 $8398起 蓴辧澳紜投資移民考團 代銷世界各國特平機票, 國內、澳門酒店及港澳船票
中環德己立街17-19號德和大厦4字全層自置物業
ticket g
EN BESA 2 2 - 1998 STO BE AN
·上海、杭州、北京八天航空豪華團 桂林、北京九天航空豪華團 桂林、華東十一天航空豪華團 華東、北京十二天航空豪華團· 桂林、華東、北京十四天航空豪華團
逢星期二、四、经 $2073
適星期二、四、日 $2480
$239012 *噸进馬尼拉,聯公,百易激瀑布高壓火山湖
蝨濤灣瀛骸辦地、翻楛、包票、大實和海瀾
•本社1972年郎巴定斷亞島,趁敦齋富,偡州最好 *馬尼拉住宿牛島大酒店喜来登大酒店·高敏事愛
灣
12.
高雄
3-846124, 3465-5
SANGANA7 197
台証$150
$3090
$3390
$3690
$3990
$4690
靼
3500 / 4
大家、富士山、李京、浙如启治笑
講髯期三五 ̇
15680
$2990
四 六
$3190
逢星期二、四、
還生期二·扫 家幫解大阪、京都、竊異、名古悅、富士山
$5650
$5130
- *6760
男紐
突出:
$ 3490
台縻,澄清湖、高雄、丁、寒温機昴玺景名聯 毛线心漫大酒店,收費 ,排入勖拖多
适繃
誌標的變催
|香港華商旅遊協會 聯合廣告
本會投訴。
本會設有質素保證耢償基 電話:五——四五八三八四 金,如有貨不對辦,可向」
Page 20Page 21