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Part I (20 marks)

Choose the correct answer (A, B, C or D) and shade the correct answer in the Answer Sheet provided.

1. Which piece of apparatus below is used to evaporate a solution to dryness

A B C D

!. "he dia#ra$ below shows part of a $easurin# cylinder containin# so$e li%uid. What is thevolu$e of the li%uid in the $easurin# cylinder

A !&.& c$&

B !&.' c$&

C !&. c$&

D !.* c$&

&. What will happen to the particles of stea$ when it condenses

A +articles lose ener#y.

B +articles are arran#ed re#ularly.

C +articles $ove at a #reater speed.

D +articles vibrate about a fied position.

. "he volu$e occupied by 1 # of li%uid water is 1 c$&but the volu$e occupied by 1 # of stea$ is

about 1&-- c$&at roo$ te$perature and pressure. Which of the followin# state$ents eplains

this

A Stea$ particles are bi##er.

B Stea$ particles $ove faster.

C "he bonds between stea$ particles are weaer.

D "here are e$pty spaces between the stea$ particles.

!

c$&

!'

!

!&

!!

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'. "he dia#ra$ below shows a chro$ato#ra$ of a fruit drin.

Which colourin#s are present in the fruit drin

A 1 and !

B ! and &

C & and

D and '

. A tea strainer re$oves tea leaves fro$ a cup of tea. Which of the followin# $ethods of

separation does it use

A chro$ato#raphy

B distillation

C evaporation to dryness

D filtration

*. A student $aes so$e crystals in the science laboratory. What should he chec to test the purity

of the crystals

A $eltin# point

B shape of crystals

C si/e of crystals

D solubility

0. Which of the followin# state$ents is truefor all ele$ents

A An ele$ent can conduct electricity.

B An ele$ent can be broen up by heatin#.

C An ele$ent contains only one type of ato$.

D An ele$ent always eists in pairs of $olecules.

&

1 2 3 4 5

colouringsfruit drink

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. "he dia#ra$s below (a2d) can be used to illustrate the followin# descriptions (i) to (iv)3

i) a $iture of ele$ents and co$poundsii) a $iture of ele$ents

iii) $olecules of an ele$ent

iv) $olecules of a co$pound

Which is the correctorder of the dia#ra$s

(i) (ii) (iii) (iv)

A a c d b

B a c b d

C c a d bD c a b d

1-. An ato$ of one isotope of phosphorus has 1' protons and 1 neutrons. Which of the followin#

particle describes another possible isotope of phosphorus

article atomic num!er nucleon num!er

A 1' &1

B 1' &!C 1 &1

D 1 &!

a b

c d

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11. "he ato$s of ele$ent 4 have the electronic confi#uration !.0.. Which of the followin#

state$ents about ele$ent 4 is correct

A 5t only reacts with non2$etals.

B 5t for$s an ion of char#e !6.

C 5t for$s an ionic co$pound with sodiu$.

D 5t has protons in the outer $ost shell of an ato$.

1!. Substance 4 has the followin# properties3

1 it does not conduct electricity in any state

! it has a low $eltin# point and boilin# point

& it does not dissolve in water

What could 4 be

A copper C sodiu$ chloride

B $ethane D sulphuric acid

1&. What is the for$ula of nicel (55) hydroide

A 7i89 B 7i89! C 7i(89)! D 7i!89

1. Which of the followin# oides reacts with dilute hydrochloric acid and with a%ueous sodiu$

hydroide

A alu$iniu$ oide C copper (55) oide

B calciu$ oide D iron (55) oide

1'. A sa$ple of pond water fro$ Bishan +ar has a p9 of . "his $eans that the water is

A neutral. C wealy alaline.

B wealy acidic. D stron#ly alaline.

1. Which two substances react to for$ a salt and water only

A dilute hydrochloric acid and /incB a%ueous silver nitrate and a%ueous sodiu$ chloride

C dilute ethanoic acid and a%ueous sodiu$ hydroide

D dilute sulphuric acid and a%ueous sodiu$ carbonate

'

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"his section consists of five %uestions. Answer all %uestions. Write your answers in the spaces

provided.

A1. A list of co$$on apparatus is #iven below.

burette gas syringe measuring cylinder

beaker electronic balance pipette

;sin# the list #iven above, na$e a suitable piece of apparatus that $easures

a) 0. # of sodiu$ chloride crystals. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

b) the volu$e of carbon dioide released durin# a reaction. >>>>>>>>>>>>>>>>>>>>>>

A!. "he eperi$ental setup shown below is inco$plete. 5t shows apparatus that can be used toobtain pure water fro$ sea water.

round$!ottom flask

Co$plete the dia#ra$ by

1. addin# a ther$o$eter.

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a) >>>Ca8 6 >>>9Cl >>>CaCl! 6 >>>9!8

b) >>>7a89 6 >>>9!S8 >>>7a!S8 6 >>>9!8

c) >>>Ba(78&)! 6 >>>7a!S8 >>>7a78& 6 >>>BaS8

A. "he dot2and2cross dia#ra$ below shows all the electrons in a $olecule.

a) State the nu$ber of protons in >>>>>>>>>>>>>>>>>>

ii) B% >>>>>>>>>>>>>>>>>>>

b) ;sin# the +eriodic "able, identify the ele$ents. >>>>>>>>>>>>>>>>>>

ii) B% >>>>>>>>>>>>>>>>>>>

c) What type of bondin# is present in this $olecule >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

d) Write down the for$ula of the co$pound for$ed between ele$ent Aand hydro#en. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

A'. "he followin# abstract is taen fro$ the article, ?What is in a ci#arette@.

2 http3www.ci##yfree.co$ci#blo#!--*-&!-ci#arette2co$position

0

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Only 60 mg of pure nicotine (contained in two packs of cigarettes) placed on a persons

tongue would kill within minutes

Nicotine is contained in the moisture of the tobacco leaf: when the cigarette is lit, it evaporates,

attaching itself to minute droplets in the tobacco smoke inhaled by the smoker. It is absorbed by

the body very quickly, reaching the brain within 7-! seconds.

It stimulates the central nervous system, increasing the heart beat rate and blood pressure,

leading to the heart needing more o"ygen. #arbon mono"ide is present in all cigarette smoke.It causes$$$$$$$$$$$$%refer to question &!b'$$$$$$$$$$$.

(eavy smokers may have the o"ygen carrying power of their blood cut by as much as !).

*ource: +mirates (ospital, ubai .&.+

a) 8ther than fro$ ci#arette s$oe, na$e another source of carbon $onoide #as. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

b) What is the har$ful effect of carbon $onoide

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

"ection B (1& marks)

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"his section consists of two %uestions. Answer B' %uestions. Write your answers in the spaces

provided.

B1. a) Calculate the relative $olecular $ass of the followin# co$pounds3

i) 978& >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

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B!. a) 8ur sto$achs contain hydrochloric acid. cess hydrochloric acid causes indi#estion.

5ndi#estion can be cured with tablets. A typical tablet contains $iture of calciu$

carbonate and $a#nesiu$ hydroide.

i) ive the for$ula of the two co$pounds in the tablet. >>>>>>>>>>>>>>>>>>>>>>>> and >>>>>>>>>>>>>>>>>>>>>>>>>>>>

ii) ive the na$es of the two salts produced when the tablet reacts with hydrochloricacid. >>>>>>>>>>>>>>>>>>>>>>>> and >>>>>>>>>>>>>>>>>>>>>>>>>>>>

b) "he reaction of nicel (55) carbonate with dilute sulphuric acid is conducted in the

laboratory. An ecess of nicel (55) carbonate is added into dilute sulphuric acid. "he

$iture is stirred constantly and then filtered. "he filtrate is heated to saturation and

then allowed to cool. reen crystals were for$ed a few days later.

i) Why is nicel (55) carbonate added in ecess >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

ii) 7a$e the #as produced in the reaction. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

iii) 7a$e the filtrate and the residue in the filtration process.

filtrate3 >>>>>>>>>>>>>>>>>>>>>>>>> residue3 >>>>>>>>>>>>>>>>>>>>>>>>>>>

iv) ?"he filtrate is heated to saturation and then allowed to cool@. What does this

infor$ation tells you about the salt produced in this reaction >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

v) 7a$e a salt that cannot be produced by this $ethod of filtration and crystalli/ation. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

+nd of part II

~~ End of paper ~~

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