Chem Worksheet

8/7/2019 Chem Worksheet

1/6

AWnuuCHIJ ST THERESA'S CONVENTSec 3 Express Science Chemistry (Past Year Examination Questions)Atomic Structure and Chennical Bonding

h0\014 6aJNov03/P3/Ql2flanteidrnortcvnHlrlltosezva\enca.(ectv?rufoatt'tihal':'Adfrrlfti;; eiliili'dnlaf op -+3"r''s 8l '

a)i) A calcium ion has an electrical charge. Explain how, and why, this ion becomes chargedwhen it is formed from an atom.ii) Give, using diagrams, the electronic structure of a calcium atom and a calcium ion. [7]

.#'";electrons.{a} complete Fig. 6.1 to describe the particles in the calclum iort.

electrical chargpositive chorge

neuiraIcha

Fig.6.1(b) How does the formafion of the calcium ion show that calcium is a metal?

{Ca ionlr5:r

t5l

Celctqrn lose i1s Zv4lnc eteth0ns {o torm (-r) ions .t1 Itc) How willanother isotope of calcium

(l) differ from !f,Ca,. . .D'Jf*nf ..119 ...$. nr$ry-r

. ..ryK-t$l... 1:nA P,.lsse .Elenqs..:qleIff.o.ru n'.S:m P.o$1ivs .iw.S

(lU be the same as $f;Ca? r A -,giivneno 4 ngII .. l]9),..$9.Y.(...9J9'!11*{)f.:1..:.1.!.. . .... . ..t21

b) An isotope of calcium has a mass number of 40. Another isolo-pe of.c.alcium has a mass' numb er'o| 44, What does the nucleus of each isotope contain? ir t3ln rrl r2, tv,n - 6A ? nl dliyy| - I+tl ,,/#f\. I I

number lrtone Caz+ ion

Pa e I of6


2/6

Nov 04/ P3/ Q9a) Atoms with two e!gq!q!g sell can combine with atoms with sevenelectrons in tFeii ouEimost shell. Draw cross' diagrams to show suchcombination. Name tne atoms and the compounds formedl BefY[iUm F\Uffide t6]b) t*o'"tn#lil"n ionic compounds win conduct etectricig,tvnlflP ims ,{ree to condqct tKiytdty

iD solid ionic compounds will not conduct electricity. t4ln6 yltbile io{tJ r not frft fo - . -.t/vlc\^e {o oncluct elecv(qNov Oil P3/ QG' Fig. 6.1 contains drawings of the nuclei of five diflerent atoms, l, J, K, L and

IJKM.

keyproton Oneulron O

Fig.6.lWhich ol the atoms l, J, K, L and M(o) are isotopes of the same efement,r$n no =somg l rM

has a nucleon number of thre6,L

(cl have one electron in their outermost eleetron shell,L (no. of Petr4' {tCtton)(d) is given the symbol lLi?

i\t1l ' -/(b)

tl l

rllI rl

t1]

L ro. ooo

I o.^, oo a" ot

t ! lrsty: J neuctroyr)Page 2 o1'6


3/6

Nov Oil P3/ QTFig.7.1showe the arrangement of elsctrons of an element from one of the Groups of thePeriodic Thble shourn on paga 12.

keyelectron anucteus @

Fig.7.1Draw in the space below the arangement of electrons of another alemenl in the oameGroup.- 0/cuP c

2- A'6 tzl(b) The element shown in Fig.7.1 reacts wlth hydrogen. Draw a diagram in the space belowto show th arrangment of electrons in the compound formed in this reaction.

(a)

- ofe- of ||ydt"ogzrtoxYOen

{av--'-=-/ W il-o{ carbcvr( Nov 061P3/ Qe n i e o{ cxrlSeh\ u) il Name the type oJ chemical bond found in a molecule of carbon dioxide. COVAtehf-----ii1 Draw a ' dot and cross' diagram to show the anangement of electrons in a carb-oridioxide molecule. Only the outer electron shells need to be shown. tnb) Substances with the chemicalbond found in carbon dioxide normally have a relativelylow boiling point. Explain why,

t3I

t3lrha covqlht rnotecu(e ie he{d +ogether lry r.reqk irte!'vnoteetpF-.+gl8sot oftracten . onry qe.,'narl 3*ynt 4 rnewJy '(*rql.rirel ro o$ncqyla1!rr wwE {rce of offruct{on .


4/6

Nov 07/ P3/ Q7Fig.7.1 ehov*a the structuregasecus hYdrogen ctlbrid- ol solid sodium chlorlde and Fig.7.2 shows the structure of

Flg.7.1solidsodium chloride

Flg.7.2ga$oushydrogen chloride {)

forca & afuactiu

keyodiurfl lon with positive cfiarge g hydrogen atom with no charge ocitorid lon wlh ncgativa charge e chbrine atom wllh no charge qp

(a) Explain why sodium chloride has a very high meltlng point..1j9(4 .irs..mqdg.$n.*....S.1)*gnq!J..ipyu ..ptnat lhil. )"{s1.,111.in..{S.n.lJb$! !9ys 9M fj$L...;:ll3 {rt.gtlKsl iqxs{Lxs :ll b,qh thesc hgt.{Lzt durolft

{b) (l} Exptain wfry sodium chloride wilf conduct electricity when molten.r!1 llDlten sfiIr.r..f9K t9.-Msyl . t31.tr. lrgJg nsp1o o,Auct etrc{ricdy t,

(ll) When allorrved to soliclify sodium chtorlde loses the ablllty to c.onduct olectriclty.Explain why,

l1^4rc n no rrroblle irlrrr to m114.t'.,gn9!...ccn9l$SJ..f !9Jlr-i31y.,,...,...(c) Hydrogen ctrlorlde dissolves in watar to form an acidic solution.

t3l

%-#ffi

Page 4 of 6


5/6

Nav 07/ P3/ Q9An element has an isotope with fte nucleon nurnhar 9,Fach of tha isotopa'e neutral etorrs hag foqrr elec#ons andtps*rt p$fide, a nucleus containing tm different(*) Sive ffre namss of lfreee. pafiicles and the. numbgr of aath partlde presenlin each nuclaus.(b){c}

Gompare the masses and compare lhe etectrical changre of these particles. l3lThs elemant has another isotope wilh atoms that have a nucleon number of ten.Compare and contrast the nuclelof theseturo i$otopes. t3]

3 This table shows some intormalion about atoms ol the elements W, X, Y and Z.{The letters do not represent th atomlc symbols of the elements,)

(i) Complete the table by filling in the information for element Z. t3l(ii) Give a reason why element Z is likely to be a metal. rlvretal and ro t0s iff valence..r:..,j:.,g..T...pgsjl.*...i.ft../.......... 11l"iiitt if "Air'+ddt1A' ih "Alinp'i .4,ir r.(ll Describe the change In elec#onlc configuration that occurs to an atom of elementW when itforms an ion.. H.fll gqln l:lq-.lpn: P. !:r* 91 l;Ifff$ d ?-3:9 rrr

(ll) The accurate relative atomic mass of element W is 32.1.Explain why this is not a whole number.. ..ffi...fr* i1 .L19 1u- .ru"n.99...*. i:ot?}.g:.., .. ..... ..

................t11Elements X and Y cornbine to form a covalentfy bonded molecule.Draw a'dot and cross'diagram to show the bonding in thls molecule.Your diagram only needs to show outer electrons.

' Frotoyl, hetfron t rsutopefl |

I a6, 5 neqtohJ I K6t?eiz t4lI 4grctons

: e-ol; e- o

{a}

(bl

xY

xe

element atomlcnumber number ofprotong number ofneutrons massnumberelectronlccorrfiguratlon

w 16 16 16 g2 2.8.6x 7 7 7 14 2.5Y 1 1 1 2 1z 11 ll 12 23 2.8. I

(c)

Page 5 of6


6/6

1

* This information comes from a website about salt't*I Cornmon Salt& S^ttcontains lhe csmp.gund sodium chloride'E n tingf* salt crystal consists of a

vast ionic lattice offi sodium and chloride ions.$wI fna lattice structure mans that salt crystals are very# *ara and have regular ehaPes.1.nI A verv imoortant usa of salt is to provlde tho hugeE "*ountt of chlorine that are used every day' Chlorine is* made industrially by electrolysis of concentrated'7,.f. aqueous soolum cnnride, This produces chforine asi an elemsnt.ft -_i

(a) The websile uses the words elomentand compound'

Na* @ cl- C

i _)Explaln what thoee words mean'eremenr . $..ryx syP-41ng..11.:1lls. *. opft .'.{: .}. 1 } *....-.jna'" Y?u@hnn. .9,g,n^,gl..qgg.t.{. -e!9:Y.,:Y..i...,. .. . .

tb) Explain why the lattice structure ol sodium chloride cau$ee the cry$tals to be 'veryhard'and have 'regular shapee" ,.T.F-ll* s .r*.{s.*P..* l-o-'$r.r\..?\?w..!ttll .iss %4 I. ion',T\4e force 4 attractiun beftveevr 0.PP..0rqJY.,,9.h9.fE:*.....(q\c...??-..Y:YS\To\nq......'..'rif anot herre +tt\e kr'rs qr ?y!W{....9.ftn.*....,.............. rzt \ )6iqnt{afrticecvytqt

etrucilre- +\^a't OMe K its l"egrtOr sharg'

Page 6 of6

Documents

Chem Worksheet