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1.Chemistry practical Answers

(1ai)

Burrette readings/cm3:|titre 1|titre2|titre3

Final readings |33.20 |49.60 |1.50

Initial readings |16.40 |16.40 |16.65

(1aii)

Average volume of acid used

= 16.40+16.40+16.65(cm3)/3

=49.45cm3/3

=16.48cm3

(1b)

(I) Concentration of Y(OH)2.XH2O in mol/dm3

Using CAVA/CBVB = a/b

CA= 0.025mol/0.25dm3 = 0.1mol

VA = 16.48cm3

CB = ?

VB = 25.00cm3

a = 1mol

b = 2 moles

.:. CAVA/CBVB =a/b

CB = CAVA*B/VB*a

= 0.1 mol/dm3 * 16.48cm3 * 2 moles / 25.00 * 1 mol

CB = 3.296/25

CB = 0.131mol/dm3

3a)

I)Desiccator- usefor preserving moisture sensitive items

ii)Volumetric flasks are used for precise dilutions and

preparation of standard solutions.

iii)Glass rod are used to mix chemicals and liquids for

laboratory purposes .

3ii)

i)Amphoteric is Al2O3

ii)Neutral oxide is H2O

3iii)

Crystallization

3b.

1. hno3aq to cuco3 solid. a light blue solid,

precipitates is formed

2. acidified kmno4 to c2h4. c2h4 is oxidized to

ethane-1,2-

diol

3. iodine solution to a paste of unripe plantain. a

bluish-black color is produced with iodine

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