Page 118 - Chemistry

makes it suitable for this use
4. The stages shown in the following diagram can be used to extract zinc from its oxide:-
Name the stage and the process taking place in it:-

C (s) + O 2(g) ZnO (s) + CO (g) Zn (s)

stage 1 stage 2 CO (g) + O 2(s)

stage 3
Name each sage and the process taking place in it:
Stage 1............................................................................................................................
Stage 2............................................................................................................................
Stage 3...................................................................................................................................

5. Study the flow chart below and answer the questions that follow:

Copper Pyrites Gas Q Gas Q

Step (I) Froth floatation,
Air
CuFeS 2 Step (II) Cu 2S (s) Air Cu 2O Cu 2S Cu (s)
Step (III) Step (IV)

Step (V)

FeO Pure
Copper
(a) Name gas Q …………………………………………………………… .
(b) With the help of diagram, describe how step (V) is carried out

6. Name the following compounds using IUPAC system
(i) CCl 4
(ii) HOCl
7. Study the information provided:-
o
Element Atomic radius (nm) Ionic radius (nm) Melting point of oxide ( C )
W 0.381 0.418 -117
Y 0.733 0.669 849
Z 0.544 0.489 1399

(a) Explain why the melting point of the oxide of W is lower than that of the oxide of Z
8. The flow chart below shows steps used in the extraction of zinc from one of its ores.
Lead (II) Carbonate Crushing Powdered Lead (II) Concentrated Lead

ore Step I Carbonate ore (II) Carbonate ore
Step 2

Step 3 Heat
Gas

Coke
Lead (II) Metal Lead (II) Oxide
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