日十月一年五七九一公年四十六國民華中
抽逖五成。:
·據業內人士拍出:本港區豉步邁,其乘務區-毎視出入口.貨運多家而定。 就出口貨品而論,目前本捻外開春帶暖銷付迅之例行旺月,一直旺至四月間,但由於世界經濟 本港段頭被爆行業,目前由於出入口貨溪煦旺未死,搬運行業鞗受权脅-工人工作表前年高期
工友收入比前減半
最近木箱搬運工價約減四分一
經濟不景出入口貨運已不如前
貨物搬運應旺未旺
萬人世界
之蛇費,羅東尼霍
在大會堂入樓 春風畫會會貝
會員作品銘
-昨天一時一大群努𥚃驳一元,包括
起睡出大會堂一气水經商,可向堅说明
八樓。內容安大厦二樓青年中心,
实已: 中區明及青年中心(安
作品公展盛况
四、精神奕奕,發現圖中;另潑墨山水,墨鵡,,水仙,竹開言及與槃。查詢電話:
修慶 李活
選、好之刷響另按,
1各天。花。燃面是
如
人
員
如瓜寶竹帳
第四二爆:龍菜
二〇太
七。子大
心汽內資
中
區
五年,心中
愛
大
汽
入
風乐
水場舞迎度
·新斑 心小組及此
份新班如下:(一
不大抑雄,用來本著一整工廠生發因為放接,故此在一般行業很編號並打包下,貨物還瑞樂器數量、博雅畫廊今天起八自此,雙行7名家庄面 遠期二龍八至十時,全 名家扇面書畫展 四、主在長 服
一拖延,一般貨物證運, 月來均普通不如理想,應旺宋旺情况極慧明躓。 由於經濟不景,外有打辨本泡幾品,水溫族,故一般外鈾标 銷貨,本年付情况,部份
,不
月現
旺
築 打 材 離
運物
外
『三月理運
二元五角*環輸至二分左右。(行) 由於行現不景,碟由勞資協商同意,工人工俱普遍降低。 據彼指出,目前公出口貨速疏落外,入口貨運包見本少。 平均一般三尺立方及卅磅以下之淫颳,過去每件工價A角-現已減至每件大角;木雜過我好中 月來普遍感旺不旺,工人每月工作量,平均較前年同期缺路五成以上。往年,一枚工人月入一 讓沙石建築材料进工會理事長郭氏推出i根據從事箱.搬運之案必會員報告,畢業工人工作 除出口貨運外,有關人口貨運- 本年由於市民消費力翮,工商,建築均秦不女,故入口貨運,
對安全操作事項的無識持高度警惕,以冤因]]。[瘗) 爲了加强建築工友,工友都要對工果意外|時忽造成永久的
·勞工 工業安全血槽
青洲英坭聯歡會
兩職工獲贈金牌
至十八日止歡迎參觀 、在湯、宋畫、吳國產,阿
濃時間,每日十時至夜七時,星期日休息。 面鏡框,一律拣恆港幣卅五无優待。地址:尖沙咀加連威老道十八虓· 百餘件 全篓工,在港是首次公爵,歡迎參觀。在展覧期間,代各配 齿、惲冰、黃山、湯譟名、楊伯興、運送、趙敬手、潘振鏟、鍾泰安、 嘆婚椒等。內容有,山水、人物、花鳥、草蟲和各班警法。該批作品共二 至六時,每月1元。 珠、胡公蔣、鱈小海、高邕、馬英、吳區、張子祥、張小茲、張開、少年班 吳孟俗、江惠汀、沈心高、汪仲山、沙山春、房毅、居牴、金心關、林妹 五晚八至十時,剪每月
分。堪稱美不勝收,其相可貴。世寬食有三天,愛好藝術人士,萬勿失此。全期三日,收卅党 友如、吳怡、吳穀祥、
書畫股資」,經出作者 畑三月,永卅 ,逢星期二:五下午四
。Cily钴他中班音
花花
(上)慈溪「花鳥」(下) 慧安「人物」
(八語
2
一 一收收出元
| 星期六下午二時一至
二四二查詢。《N
·二四二〇七一两块五 。欲知,精武戏的
元。有意者,請速報名
十時-全期兩月11
:八糖
「各機樂器,全期1月收
怪交:
WAH KIU YAT PO
報日橋弄
REFERENCE LIBRARY
JAN 1975
示提友工向處工勞
HALI. 五期星
自據,營據明除
式方作操全安築建
有人工化交頁三第張五第 日八廿月一十年寅甲屬要
操作,帶以減少意外的 黎大、陳鐵,長近獲得公司董事局主席活符类。
·兩位會任職青洲英品有限公司五十年之录工
村口邊椽
外意免避意注程工土挖及棚搭
發操及時一安中越 生作可所鶯全
以致藏整會內通工作加
高程賴作說並介
安類防
:
:物除會
史。張獎儀式在聯歡會舉行,該聯歡會有三百草, - 頒授金牌紀念。青洲英泥有限公司有九十年歷
意作的安全力法有能籍介
說明書:對各項日常操
並附有安全操作指南的
, 介紹各類安全 旅外 布米加3活特和陳
下
· 或其他安架,必須築
良好,並須有足够支持
意書用以撑洞穴,坑 :抄土工程... °C
霆鵡任何部分之木架
免.高處墮下說明的摘錄。
避程,佩榮杰搭和人在 紹,下面是有關挖土工
,以防失足跌下, 以告示向行近之車輛提 年可再起爆炸之雲悅。金腰帶給予高空工作之
·搭拆綳 工人。另一方面,工天 盧確保該地點並無可範圍內·赢提供安 工程開始之前,督導員】作之人員。(五)在盡 出警告。(五)在挖掘之站立線給予在高盛工 棘,應圍以迷當之中和【注意良好之嚴房管理。 一向穴邊線附近堆放物科(三)工人可能因拌機 力。(二)洞穴,晏坑隧道內之所有空來, §四ÿ在貼近剂口逐,而從高處墮下,故應 必須安裝牢固, 以發意外鬆脫。八三一不在 (四)提供牢固及適當
臺遞
座位
̇導棚
一一一
| 棚架覆在有資格人员督 應備有當之升降設備 有人督亦應將其佩帶。(*)
rema
改正不良習慣 不要做垃圾蟲,隨由於隨便,有熱,沒有
爲自身和家庭計,
宏外梨脫。(四)工作 保持各部分牢固,避免 趣架必須保持安警,並
·有足够支撑力() 材料必須品質良好,且 【成拆卸。〔二〕棚架之
在輪演中,公用軍輛中,馬路上.若干的食店,我們可以常常見到 公德心與習術所做成。: 損及他人。垃圾之所以成其拉
垃圾虫最令人討厭的,因他
堅道明愛青年中心定期辦
露天青年西方土風舞之夜
坚唱演的任
辦生心中術藝
頌
俩的,另
燒乃由志榮邀。
歌詩徐
學師·集和六故二小有的之要中他無三欷、 內家名。六本事部說十作一的國是疑:有詩小 吉林的世木·時事短,三品。作數當問。家人說欲
[喵敎于崇基學院音樂
晚會,是十四晚八時 艾。徐詩歌朗 時在踏之樂曲。鋼犘伴
在藝術節演唱兩場
著名中低音斯義桂
故明愛青年中心,特於研習土風舞之興,是以色列之求,希臘門羹。 |分土風舞之夜甚爲成功 辦第二次西力土民 以結他女,世界各地,在國際大厦十一樓 ,經各靑年要求再辦,之夜。佈此提高實年人 土風舞介紹等。例如,德學院小音樂器,不收 年八月三日所舉行之西十分,遮打道木球會 整,包括:畢位舞酎 於七宮本月十八日,七時四一高康收治點,該洗程序
.....男中低音斯養棣,將在本
周藝術節中,演出兩天。
門券在大會堂票房發售 見各屆賽後節,
麻國括者 更藝盘)
平台必須最少有兩呎網,吸到將盡的烟蒂,不把火頭弄熄,隨便亂扔,除了造垃圾之外,过容,如人&
由,處以雅狀,實在咎由自取,活該! ,並在台違配以“板及易 一日燃烧了易底火的物體,便引起火警了。前些時,被坭的垃圾
三高之擺桿。五
不雅觀。平而論,有痰應該吐,不然的話,若不由喉吐出,吞入肚中,
機弗道及所有會從他人,這就相當於晏相損害他人了。,
||在森頤下之地方融安爲
·及最少的害之镰棒。 出要发加以改正(阿)
度,並應固定於正當之 不自我來一下,避損人呢?
【遵楓。〔二)所有工作 在地上,路的人踏聋會滑倒+
實體有足服之間以及多種不聽,而學 工友如能自愛
要送蘭,我今影家 何 人論讓機樂 天响如人唱...貓界 何如的果在。西他意,精 不果。愛燄他洋在等鹱英
次樂際
:唱開 覺閒 等去演
時歌 在身心病 得的 國齡球
演的 福智非地 家庭
興,斷:站示多 釉最 斯定。見
及 院真 術立;抽對電氏演
曲
樹靈
。
蛋午星
主唱曲的在
至一萬智 八日
强時 推同一
炭在
月節配煮
腰。,外聲英共名雇寫:會時
遜懟 相˞賨蓫節 衆高 詔在神 英瓦 與 唱歌藝於中 揭俄貴。,演與者 庶天在 “格晚霜獸 有楽任解並的音能唱能招樂。
KGE
XXC
IL D75
中學會考專欄
化學科(九)·陳湛杰
CHEMISTRY (#9).
Holutione for Chemistry 《#8)
Jultiple Choice Questions
2.(D) 3. (D)
Conventional Questions
E
ln(a) Preparation of copper sulphate
ozystals from, malachite.
AB
malachite le basic copper carbon- ate CuCO3= Cha(OH)2 occurring in nature and copper sulphate crystals exist as the pentahydrate **OuS04.5120, the carbonate has to
be converted into the sulphate. Carbonto aoid being a weaker soid than sulphuric Boid, carbonates. ware readily dacofposed by excess
dilute sulphuric acid. wita
Thus agolution of carbon dioxide. malachite is treated with dilute
ulphuric acid which first reacte ::with the copper hydroxide (Cu(OHz)
and then the copper carbonate
Cub03). Using litmus as indicat only a slight excess of dilute agi is necessary for complete
gction:
*y*Cu(0) + 2H_S04
·CO2↑+3H2O
Opon concentration of the resulting lution of partial evaporation of inator, and cooling, copper Bulphate pentahydrate will separate. These crystals can ther pe Platered and carefully. dried with filter paper.
if (b) Preparation of ferrous
¡Pulphate crystals from iron wire.
rystalline ferrous sulphate Touchure as the stable heptahydrate,
7820. Iron being above en in the electronegativity series will displace hydrogen from dilute sulphuric acid. Although found with idation atatea II and III for
in the reaction conditions iron with. aulphurio acid, the environment is strongly reducing 1 dva to
hydrance of nascent
of
dogen). Thus it is the ferrola etate which peralata under those coniitions. To prepare the salt, the iron wire is dipped into a quantity of dilute sulphuric acid which is almost sufficient to completely dissolve it:
F + H270 → H↑+ FeSO4 Mhis is followed by filtration and
then evaporation, the latter
process Berving both to
concen
trate the solution as well as to drive off any dissolved oxygen which might later partially oxidize the ferrous ion to ferris ion. The consentrate is then allowed to settle for crystal- lization.
(c) Praperation of zinc carbonate from metallic zinc. A solution containing, zino ions is prepared by dissolving Zino in dilute Bulphuric acid se
Za + H2 50 - 2504 + H
Zinc carbonate being an insoluble salt may be prepared through precipitation reactions. However, with carbonates of less electro- positive metals such as zinc, sodium carbonate solution will produce a mixture of hydroxide and sarbonate (baeio zinc carborato), Therefore the precipitation reaction met he proceeded with the use of sodium bicarbonate:- Zn30+ NaHCO3 - 2000, +
4
N2504+
20+00
(d) Preparation of mire lead wonoxide from a mixture of Jead monoxide and cupric oxide.
Lead monoxide is different from cupric oxide in that it
amphoteric readily dissolving in acida and alkalis. Thus it may be seperated from the latter by using caustio alkali, when it dissolves as the plumbite, leaving cuprio oxide behind The enlution 18. filtered, exess of dilute nitrio soid added to gravert the reaction mixture into lead nitrate solution Lead nitrate is readily crystal- lized/without water of crystalli– sation.
Pure dry lead monoxide is obtained upon careful heating of the lead nitrate crystals:-
*Pb0 + 2NaOH - 2NaPbO2+
2Pb(NO3)2 → 2PbO + 4NO2↑+ 07
1. (a) When chlorine water is added
to a solution of Fotassium bromide, bromine is diepladed by the more reactive chlorine. inrarte a brown odour to the aqueous mixture,
CL+, 2KBr→→ 2014 Br2
This
However when this is shaken with carbon tetrachloride, bromine being more soluble in the organic solveri will be readily extracted for the
The dolution of. aqueous nyer. bromine in carbon tetrachloride. being orange in colour.
(b) When ferrous siphatasoluti ja heated with nitrie said in the presence of sulphuric acid, it fimt reduces the nitric acid to nitric oxide and is itself oxidial to farrio sulphate:~~
6FeSO4 + 2HNO3 + 3H2SO4 + 2N0+ 41,0 3Fg (804)3
Bitric oxide readily combines with the remaining ferrous sulphate to yield a brown compound, nitroso- ferrous sulphate, with the formu FeSO4. NO. The heat of reaction, however, may be sufficient to of@ee decomposition of this compound with 1iberation of nitric
oxide. The nitric oxide, when comes into contact with air is readily oxidized by atmospheric Oxygen to form nitrogen dioxide,
a brown gas:-
2NO +0
2N021
The ferrio sulphate solution formed 18 pale yellow in colour.
(b) Copper sulphate crystals are blue in colour with five molecules of water of crystallization per molecule. Since concentrated sulphuric acid has a strong affinity for water, it is derable. of removing this water of crystal- lization, rendering the copper anlphate, to be converted to the: anhydrous stats which is white.
'Cu50g.520
(hydrated)
5H20(H280g)→ Cucy
(anhydrous)
Since concentrated sulphuric acid has a high concentration of sulphate ions, due to common żon effect, copper sulphate has only a Thue low solubility in the acid. the majority of the anhydrous copper sulphate does not dissolve.
Questions for Next Week.
The questions in this issue are related to 2.3. Acidity and alkalinity. Study your notes and textbook before attempting the questions.
Multiple Choice Questions
1. Which of the following indi-
cators in suitable for titratior:
of vinegar with sodium carbonate solution?
A. Litmus
B. methyl orange
C. phenolphthalein.
D. Universal indicator
E. none of the above
2. A solution of hydrogen chloride.
in dry toluene dan
A conduct electricity
D. react with carbonates
C. react with ammonda gas (dzy)
D. react with zinc, magnesium and
iron
E. pone of the above
3. Cheng grades of common aait do
not "run" when expose to air for sometimes because
A. Bodium chloride is deliquescent B. calcium chloride is deliquascert 0. magnesium chlorido is
delique agent
D. sodium hydroxida in deliquescort E. sodium chloride ie efflorescent
4. A sample of armonie gas con-
taining moisture may be dried (" by passing through the following drying agent: -
A. concentrated sulphuric acid
·D. fused calcium chloride d. quicklima.
D. Phosphorous pentoxide
E. anhydrous copper sulphate 5. A 0.45 g.sauple of an acid
having an equivalent weight of 75 was titrated with standard. babe. It was found that the percentage purity was exactly 45 times the normality of tha bage. Whet volume of the bere we.a used in the titration? A. 27 ml. B. 270 ml. 0.2.7 liters D. 2.7 mi. E. none of the above
Conventional). Questions
1. (a) What is the concentration of
a solution formed by diluting 300
of a solution containing.0.1 icle Cof. HCy to 6 11tere? (b) Ka h
congartration of HCL in 500 m. of a2M solution the same as the concentration of HCl in a solution formed by dissolving 2 moles of the aaid in 0.5 liter of solution?
GET OF BOJI (c) Which of
of the following is
ia the more dilute solution of BH Car (1). 250.01 of. M. solution or (2) 0.1) mole of solute dissolved in 250 ml. of Qlution? (d) 250 ml; of a 0.1KB) solution of 201 Bre diluted to 1 liters (1) what is the no. of the solution no.
so formed? many grwin equivalant weights does: each solution contain? (e) 50 ml. of JM HClare mixed with '20ml of 0.5M HOL. Calculate the normality of the resulting solution. (Assume: volumes are additive).
BUR
2. The neutral color of litmus is violet, in acidic aqueous solutions it is red, in basic aqueous
What color solutions it is blue. would litmus be in an aqueous solution of each of the following? Explain, using equations as well as | words (a) NaÖH, (b) HCl, (c) Na20,
(e)
(n) H1
(女) 【RHCO3, (5) GHS, (a) K2803 (n). NH4NO3-
(975:
物理科(九)·醴禾燥
PHYSICS (9)
Solutions for the last issue
1(a) Mass and Weight
Mass is a measure of the in- ertia of a body. The mase of a
Mass is measured body is constant. in kilogrammes (kg) or grammee (g) by. mearia of beam balances. Mass is a scalar quantity.
Weight of a body is defined as a force acting on it due to the gravity. Weight is measured by the product of mass and the gravitation
Since 'g'' varies with
acceleration of a place tudes and of a body is the weight of a latitudes,
not
value.
i V a constant
value aries with 'g' The_unita of weight is the same as that of force it is measured in newtone or kgf, by spring balances. Weight is a vector quantity.
(1) Mase of a body, m = 10 kg
Gravititional acceleration n the moon,
包 = 1.8
Its weight on moan mg
= 10 x 1.8 = 18 Nor 1.8 kgf
(11) To achieve an acceleration of
a 1.5m/s Force required = ma
10 x 1.5 -15 N
1.5
kgf **N=4¤g
(iii) Friction, f
*
0.5 x 10 x18-
.9 N or 0.9kgl Force required to keep it in uniform motion, a 0
,(F - f) = ma = 0
F9 N
(iv) As the speed is constant, add-
tional energy, required is con- verted to potential energy.
月期四
Its kinetic energy is unaltered
Therefore, additional power developed:
APA mgh,
「
(b) 4
10-
=9 watti When the lift is as-
cending with:0
A+ .U = mg = max0
Timg (1) where T is the balan-
ce reading, Vis the upthru
at and
mg is the weight. of the mass
The mans displaces my of water, therefore weight of water displaced
= mig Consider the liquid in mos tion, un'gm'a = 0
(11) U... =mg Substituting (11) into (i)7:
+ m'g = ng
is The.
uniform 27 cross-860-
"The tube
volume of air trapped tion aan be measured by the length of of the air column.
TFV - P。。
Erect the tube and the metre rule with open- end upwards, as, shown. Record the adr column The pressure of the air inside is(p。 + h) cm Hg PV = (Fe + bil By Boyle's. Law,
FV = constant
(po + h) » Polo
··P2(C。 - ()= h
(a) Let v be the volume of gas
escaped at 100 cm Hg pressure. {7 - vitre of ges at 100. cm Hg remained in the cylinder And this remained gas occupied, the whole cylinder again with a reduced pressure. Therefore, by Boyle's Law
(5.
= (5-2)8 N
(1号)50.
30 N or 3 kgf
(b).
(i) When ascending with
a = 2.4 mè
- (1) For motion of water of masa m* displaced by the body
Ung n*a.
¤§= (a + £)...(2
Note: Archimedes Principle doen
not apply to accelerated liquid. U 卢梭
Substituting (2) into (1),
T = m(a+g) - m*(a+g)
+8)
5(1)(2.4 +10)
37.2 or 3.72 kgf
(111) When descending with a-2.4
ing →
想
Tag = ? SU
—
= n(g_e) = U... For motion of water dis- placed, m
'g
(3)
U = m*(ga) ...{4} Substituting (4) Into (3),
T= n(g-á) = m2 (g-a)
:=(mm)(gua)
= (5-25), (10 ~ 2.4)
= 5 x x 7.6
23.1 N or 2.31 kgf (iv) If the lift fails freely,
with a g, theri
mg - U - TFB
(5)
and. for motion of watery weightlessness occurs too;
»'g – V = m'a = m'g
ប
Substituting into (5),
(b) Introduce some mercury into a long capillary tube. Place the tube horizontally and sealed one er of it by heating.
„Á metre rule is attached.
Measure the length of the mercury pellet and the length of the. air column. trapped.
The pressure of the air trapped is the same as the atomspheric pressure, Pa outside.
(1) 100 = 1090 v1litre The escaped gas expanded under. a pressure of 75 cm Hg., Bo it became.
V
10075 V
V = 4/3 = 1 litre
with water
lead shot with ba
28-55" water
W84.7
shot +
Wt. of bottle water
remained
Wa = W = 56.2 E8
Wt. of water displaced
* Wq = (W3− W2)=2-5 gt
B.G. of lead - wt. of lead shot wt.of water die- shot
placed
= 11.4
Questions for this week:
1 (a) Describe a simple form of (1) constant-pressure gas
thermometer, and
(ii) constant-volume gas ther
mometer,
How is centigrade temperature defined on the scale of these thermometere?
(b) If the difference of mercury
level in a
in a constant-volume air thermometer ie -2 cm when the temperature of the bulb is 10°C and +22 cm when the bulb ie 10000, what 1日 the height of the barometer?.
(c) A hot air balloon with fabrio
of 20 kg can lift a load of 180 ke-at ground level where the density of air is 1.2 kg/m3, the
750 pressure is mm Hg, and the temperature 17°C. If the tamp- erature of the hot air is 227°C (i) what-ia the volume of the balloon? and (ii) what load can it lift then?
2.(a) The linear coefficient of exe
paneton of braea is 18 x 105 per deg C.
(1) What is meant by this ex- pression?
(11) Calculate itp value per F (b) show that the coefficient of:
cubical expansion of a
homogen-
ous substance is three times it coefficient of linear expansion. (0) A barometric height, as read
at 12°C by a brass soale correct at 0°C, is 76.52 cm. What is the actual height of the mercury column?