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5.2 TEST MS

1. (a) (i) Equation Na 2O + H 2O 2NaOH (1)

pH 1114 (1)

(ii) Equation SO 2 + H 2O H2SO 3 (1)

pH 25 (1)

(b) Covalent oxides acidic solutions (1)ionic oxides alkaline solutions (1)

[6]

2.

(i) Mac o!olecula "#iant covalent"#iant !olecula

(ii) Silicon"Si

(iii) e$#$ CaO + SiO 2 CaSiO 3 %ase%alanced

[4]

3. (a) (i) SO 2+4

(ii) 4& + 5O 2 2&2O5

o &4 + 5O 2 &4O1'

(b) (i) %

*e *ave lo, !eltin# -ointso t*e e a e ,eak van de .aals /o ces bet,een !olecules

(ii) 0dd ,ate o *eat in a /la!e

est -H c*eck /la!e colou

13"14 ello, [9]

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(b) (i) 0!-*ote ic (1)

(ii) uation ,it* NaOH

0l(OH) 3 + NaOH Na0l(OH) 4"$ Al%"&' #%&( "' # ) "&

* [Al%"&' 4%&( "' ( ] * ) & ( "

"$ Al%"&' # ) "& * [Al%"&' 4]

*

R identi/ied as 0l(OH) 3 o 0l(OH) 3(H2O)3 (1)0 balanced e uation (1)N.B. Allow e+uation with si co,ordinate Aluminium and u- to

si "& * ligandsN.B. Allow e+uation mar if /%"&' # given in a balancede+uation

uation ,it* H 2SO 4

20l(OH) 3 + 3H 2SO 4 0l 2(SO 4)3 + 7H 2O

O< 0l(OH) 3(H2O)3 + H + =0l(OH) 2(H2O)4+ + H 2ONB Allow e+uations with si co,ordinate Aluminium and u- tosi & ( " ligandsNB Allow e+uation mar if &%"&' # given in a balanced e+uation

Co ect 0l s-ecies as - oduct (1)0 balanced e uation (1)

(iii) >a #e lattice ene #o st on# covalent bondso Hsoln is ve -ositiveo ? is ve -ositive

o su! o/ * d ation ene #ies less t*an covalent bond ene #ies (1)[01]

(c) &4O1' is a !olecula (st uctu e) o si!-le covalent (1).eak inte !olecula /o ces o van de .aals /o ces (bet,een !olecules)(1)SiO 2 is a !ac o!olecule " #iant covalent " #iant !olecule (1)

Not giant lattice

(St on#) covalent bonds (bet,een ato!s) !ust be b oken (1)[9]