Page 151 - Chemistry

You are provided with:
- Solution A, sodium hydroxide
- Solution F, 0.2g of a carbonate (MCO 3)
- Solution B, 0.5M Hydrochloric acid
- Phenolphthalein indicator

You are required to:
(a) Standardize solution A with solution B
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Using a pipette and a pipette filler place 25.0cm of solution A into a 250ml conical flask
Add 2-3 drops of phenolphthalein indicator
Record your results in table 1 below
Repeat the procedure two more items and complete table 1
Table 1
I II III
3
Final burette readings (cm )
3
Initial burette readings (cm )
3
Volume of solution B used (cm )

(a) Calculate the average volume of solution B used
(b) (i) Determine the moles of sodium hydroxide used
(ii) Calculate the molarity of Sodium hydroxide
Procedure II
3
- Place all the 0.2g of solid F into a 250cm beaker.
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3
- Measure 100cm of the 0.5M hydrochloric acid solution using 100cm measuring cylinder and
add it to the solid in the beaker.
- Shake well until effervescence stops; label this solution C
3
3
- Pipette 25.0cm of solution C into a 250cm conical flask
- Add 2-3 drops of Phenolphthalein indicator
- Titrate solution C against solution A
- Repeat the procedure and complete table II below:
Table II

I II III

Calculate the:
(a) Average volume of solution A used
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(b) Number of moles of hydrochloric acid that was in the 25cm of solution C used
(c) (i) Number of moles of the Carbonate in 0.2g
(ii) Relative formula of the carbonate solid F
QUESTION 2
You are provided with:
o Solution D, 0.25M Sodium thiosulphate
o Solution E, 2.0M Hydrochloric acid

You are required to:
Determine the effect of temperature on rate of reaction.

Procedure:

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