頁四第張五第日七廿月二十年丑癸歷
WAH KIU YAT PO
“水、酒精,三硫化碳,四氯化碳 汽油
(4)溶解度曲线之用處,
六期星
日九十月一年四七九一屦公年三十六國民華中 育教僑華
Four commercial uses of carbon dioxide:
in fire extinguishers, because the as 1 heavy and will not sunport burning..
used as a refrigerating gent in the form of dry: ice.
in making areated water.
4. in the Solvay process to manus
facture of washing soda,
The annaratus just before the reaction takes place is show below:
Action,
of water on ouicklime When water is added to quicklime. there:
e is usually hiscing sound:: great: heat is develoned; steam显然 riven off; the line cracks and " uffs up and finally crumbles to a powder about thrée times as hulky. This is slaked lime.
If insufficient water is edited slaked lime to dissolve all of the latter to form lime-water then a milky liouid is obtained which contains lime-water with solid marticles of slaked Time
橋
DE
管底,再將温度计抹乾,插入試管中,當慢 质剛好°C将迅速特上層飽和溶液的大 「部分:倾入一已挤過的蒸發皿中,而使未落之 | X及小部分之飽和溶液留在試管中。
(d)常用溶劑:
1974 中學會考試題預習專欄
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(6)求飽和溶液中含x之重量、
化學科(甲)
林景源
(可一望其曲线印知
溶解度.
测驗五解答
甲部
選擇题。
將合飽和溶液的蒸發皿再準准拌過照 | 後記在一個水之境拉上,間接加熱,用境
·中的蒸氣,符洛液氮乾。為使水份完全蒸發 「可將蒸發皿的底部抹乾。置石柿網上,用本 主が熱冷却後、再蒸辞典 加固体人之重量。
丁利用溶解 度曲线和各款之溶解度,然後可用分 部红晶法使它們分離.
5將30g扒酸鉀及20克氯化鉀 混合物以70°C之水100克溶解心,燕国 体剩留,因70°C将氯酸钾之溶解度為 32克,氯化钾為48元。
-install Carbon)
cht of carbonate used
76.73-67.93 = 8.4 gma
welcht of carbon dioxide evolved.
= 76.33-74.95 = 1.38 gC.
whence; nercentare nf carbon dioxide in the carbonate.
1000 16.4%
Carbonates and bicarbonates of、 alkali metals:
They are made by the action of carbon dioxide on alkalis, eg,
CO + NROH : Na2CO3 + H2O
Excess of carbon dioxide.wi cnnvert the carbonates' inte bicarbonatessica
D
3BWA
OC OE
© C
03
OB
1
OF
@B
AD
B
(C)計算溶解度,将蒸發皿及飽和高 重诚公蒸發皿及国之重量,即可得此飽和 溶液中含水之重量,將蒸發皿及固体x之共重 诚去蒸發回之重量,所得比飽和溶液中个人之重
Carbonates and bicarbonates
eparation
()填-
題
將此溶液冷却至20°C時则有说服
1消發
2強鹼,二氧化碳,白, 碳酸钙
溶解度 =
我飽和溶液中含水之中量
3氧化鈣,二氧化碳
肉鈣、鎂、鉄之碳酸氫鹽的. 鈣鎂,鉄之硫酸鹽或裁化物的。
中央20天氣化钾則至影响。
2解
由溶解度曲线得到:
下期福習範圍:
5人造沸石(交替砂)
在10°C将每100克水可溶解56.说裁军
稿類及解颗之一的性質。鹽類的梦
6過滤
4白,结构水汽化而放出.
3倾泌
3蒸發
在20°C将,每100克水可溶解弘无碱化钾,法,氯执化载盟酸之製法性變 又每100克水冷却液可柯出 22.7克裁化鉀 。 及普通用途,食望及其他氯化物,漂白用。
花140°C時100克冰+56.7元文化課
56.7克、飽和溶液
10芒确,10
在100°C時20无飽和溶液中含
1974 中學會考試題預習專欄
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堅道書院主編
2增加減少
100 756.7
12.8克水
化學科(乙)
(十)王兆文
@過飽和!!
128 x
22.7
1:00
29克氯化鉀
Carbonates and bicarbonates. of. heavy metals:
The carbonates of heavy metals: are insoluble and can be prepare by precipitation using either sodium or potassium carbonate.
·MC (NO3)2
+
Na CO
Solutions of the bicarbonates. can be obtained by passing: carbon dioxide into aqueous suspensions of the carbonates. of metal:
CO.
LHCO
suspending in the liquid. This
milky liquid is called milk of lime Chalk and quicklime compared:
Chalk
white
ne taste
Quicklime
white.
burns the tongue unpleasant and bit taste.
decomposes whenio change on heating heated
addition ad water basing. effect:
no effect on I moist litmus.
much heator^duced. on addition of water
mosit litmus is turn ed blue
effervesces: much heat is produce when HC1 18: but no effervescene added, owing to.caO+H=0. evolution of. sarbon dioxide.
Uses of Time:
Ca(OH) +>HC)
CACT
1. For soil treatment.
2. Mortar is mixture
water and sand.
3. Cement is a mixture of calcium
silicates and aliminates made by strongly heating a mixture of. Climestone and clay. When mixed with water; it gradually sets and hardens,
Wie harder
Calcium carbide is made by stran ly heating a mixture of onlakiin and carbon in an electric furnac
Cao +.30 - a Cao, Ch
5. Common glass if made by fusine soda-ash and puicklime, with excess of sand.
Na COS 0 BaO + SiO
Na
Casio z
4澄谲,混濁、澄清、混渴
5碳酸钙
OM.
乙部
在一定温度下,飽和溶液中每100克 溶劑所含溶質之无数,搏為核济资验 該温度下之溶解段。
溶解度。首先應製備在丫足時入的飽和 【溶液,然後再求一定量比飽和溶液中x
之重量即可针得其乐比温度的溶解度。
(a) 製備在发情x的飽和溶液
温度计
未溶解之
-攪拌棒
强上圈装置,將試管裝約子滿蒸餾水 「慢慢加熱到約比丫度高5°C左右,同時 [逐漸投入粥細的X並不斷攪動,直接 【試管底部出现一些不再溶解之x為止。當 温度熱至比丫度高出5°C左右後,將本生燈校 去,讓塊杯慢慢冷却,同将繼茨揚動。溫度) 【跌近丫皮将,移去攪拌棒,讓示洛的x沉到
128克水冷却没打析出
(6)解.
50元的記和济液否谗笑10元即 黃和无水在此溫度能溶解溶资10元,故 其溶解度為:
10 = 25克
40.
(a) MG (HCO3)2 + 2NaOH-
Mg CO 3 & * N12 CD3 +2H2O
<b> CaCO3 + H2O + Co. -
Ca (HCO3)2
(e) 80+ NaCO3
CaCO3↓+ Na280元
(d) CaCO3 + 2HC
°C.Cl + H2O + coz个
(e) (a(HCO3) + coun
2CaCO3↓+ 2H20
@(a)易潮解的物質
氯化鈣,硝酸鈉,碘化鉀. 硝酸銀,氫氧化鈉。
(6)易风化的物質..
芒哨,藉打,明礬、硫酸銅 結晶硫酸亚铁結晶。
(C)結晶体
.食鹽結晶,硫酸銅結晶(CuSO 560),硫酸亞鉄結晶(Fe80 TH20), 硫酸鎂結晶(My80x720),硫酸納 结晶(No80、10H30)
CHEMISTRY: (LO)
Suggested answers for Lastweek.
(a) A burning tanes is etting. uished when surrounded by
tha Vas. This reaction is used to control the filling of the gas jars.
(b) When strongls burning.
magnesium ribbon is lowered into a far of carbon dioxid it will give out so much -heat that. the gas decompos es and the metal.continues to burn in the oxygen hat produced. Black specks of carbon are formed and a white ash of magnesium oxide:
CO2+ 2MG - ?MrOf + Cb
As an acidic oxide, carbon dioxide reacts with sodium hydroxide solution to form first sodium carbonatrand: then sodium hydrogen carbon.
201
PHCO
If the sodium hydroxide solution is concentrates white not. will be formed during the second stare. because sodium hydrogen
·carbonate is only svarinely. soluble.
The proportion of carbon a dioxide in the atmosphere remains anoreximately const ant because it results from: the balance between those processes which produce it and those which remove it from the air, but recently nollution has increased it
by one-third.
The atmosphere Pains carbon dioxide by
the respiration, of all living OrEAN BNS
2. the action of bacteria upon
animal and niant residues i the combustion of all common fuels,
4. fermentation and nutrefaction:
Carbon dioxide is removed. from: the air by
1. rain and ocean water dissolv
ing it,
2.the photosynthesis of carbo-
hydrates by green plants in sunlight,
3. the weathering of roaks' which
results to the fromation of soluble carbonates and blcar-
bonates.
Properties:
State
carbonated White crystal: line solides:
| carbonates of
sodium; potasn ium and amon ium.
Camoronoust
carbonates of rheavy metals.
bicarbonate
solubi 411 insoluble,471 soluble Jity except those
of ya: K: and.
Acton Usually des of heat composed at
high tenner ature riving
the oxide,
Readily de-
Jomposed into.
carbonate、and
Jaarbon dioxide
CaCO3 → C2O+CO2 Ca(HCDS), Calls
...
(MagCozand
K2003. not.
affected by heat)
Action CO evolved. of HC)
dilute
Carbonate may then further decomposed. Hinto oxide and carbon dioxide.
evolved.
of any &CO, TRHU Tack NaHolz + He +HO+CO
acid
-Nuce +M2O
200+
Effect | Tmmediate not No not. of add because Mico, because
ing solis insoluble3 MECHCO,)
of Mesq
How to 1 distim uish
pot, on boil ing becaige
becomes MrCG
*H + C,
Action of gently heat, sagt On::boiling÷withtwater the bicarbonate but not th the carbonate, would give: carbon dioxide. ...MrSD. test.
Calcium carbonate and related compounds:
Calcium carbonates occurs in nature as chalk, limestone, and marble.
Effect of hent: calctum carbonate when heated adves auicklame:
CACO
Question for this week:
Describe an industrial process. (Solvay Process) wherery sodium
bicarbonate and sodium carbonate are manufactured.. Indicate any important physical princizle ed.
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Sujltek (10)
b. By USING *Queations". #-
鄉持雅
This is to raise the interest or arouse suspense of the readers by quest→ ionings. The questions need not be long. but must be planned cleverly enough to tempt or to inspirit the desire of the readers to explore for the answers throughout our essay. To begin, for exampla, writing on #Should Capital Punishment Be Abolished? Discuss.", the introduction can be made in the following
Should a killer be oondemried to the pena- 1ty of death? then we all become killeray| but, if the bad is not relentássly punished," will the fast growing of crines comes to be a more serious social probler The readers, undoubtedly, will feel like to find out what our suggestions are The following is another example of intr- "oduction to topics such as: "My Career",
"A lady!a Job", or "Nursing":-
Have you ever heard of 'a lady with a lamp1 à lady, who gave comfort to the. wounded, homaaick, and miserable soldiers who orowded together in dirty and filthy Toons of aƐamall hospital which was alway in laçk of medicine and equipments? Man it not Florynos Nightingale, who was ofte referred to as the Angel in White!, the first lady nurse in the army?
*. By using iquotationstil
Quotations can often be made from well-known speeches, poeng, books, idioma words of famous people, the Bible, or aver from plays, and verses of songs. It is important to remember that the more familiar to the readers the quotation wa make, the better and the more affactiva 'it will be.
Fo be contd.
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