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1. a) Name the apparatus shown below.

..

b) What error has been made in its manufacture?

..

2. Hydrogen can be prepared by the reaction between magnesium and dilute hydrochloricacid.

a) Name another metal, which can be safely used instead of magnesium...

b) Give a test for hydrogen.

Test: .

Observation: .

c) Hydrogen is less dense than air. Which is the better of the two method shown below tocollect the gas? Tick the correct answer.

d) Can hydrogen be collected over water? Explain you answer.

Answer: .

Reason: .

e) An excess of hydrochloric acid was added to 0.20 g of magnesium. (A, of Mg =24)Calculate:(I) the number of moles of magnesium used in the experiment.

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(II) The volume of hydrogen which should be produced at room temperture andpressure (r.t.p.) when all the magnesium had reacted. (Molar volume is 24 dm3 at r.t.p.)

. dm3

f) The student collected 180cm3 of hydrogen from the experiment. Calculate thepercentage yield.

3. A student electrolysed molten zinc bromide and dilute sulphuric acid in the apparatusshown below.

a) What was produced at the electrodes A, B, C and D?

A:

B:

C:

D:

b) What happened to the brightness of the lamp when the following changes were madeto the experiment?

(I) Water wad added to the dilute sulphuric acid.

.

(II) The heating was stopped and the apparatus was left of cool. Explain your answer.

Answer: .

Explanation: ...

5.

a)

A student recorded the results of four experiments with ethanol. Which result was notcorrect?

a) On reaction with acidified potassium dichromate (VI), the colour of the solutionchanged from green to orange.

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b) On combustion a gas was produced which turned limewater milky.

c) The ethanol dissolved in water

d) On combustion a gas was produced which turned limewater milky.

6.

a)

A student did four tests on the fertiliser ammonium sulphate; F. Which test did notproduce ammonia?

Aqueous sodium hydroxide was added to F followed by a piece of aluminium foil. Thesolution was warmed.

b) Aqueous sodium hydroxide was added to F and the solution was warmed.

c) Dilute hydrochloric acid was added to F and the solution was warmed.

7. A student found that a hydrocarbon, P, contained 85.7% by mass of carbon. What wasits empirical formula?()

a) CHb) CH2c) C2Hd) CH3

8. This question is in two parts.

A student was given a substance, M, and was asked to identify M and to determine itspercentage purity.

The following table shows the test on M and the conclusions made from theobservations.

Fill in the mission observations and identify M.

test observations conlusionsa) M was dissolved in dilute

hydrochloric acid and theresulting solution dividedinto two parts for tests (b)and (c). Any gas producedwas tested.

M is not a compoundof a transition metal.

M contains Ca32+ ions.

b) (I) To the first part,aqueous sodiumhydroxide was addeduntil a change wasseen.

M probably contains

Ca2+ ions.(II) An excess of aqueoussodium hydroxide wasadded to the mixturefrom (I0.

c) To the second part,aqueous ammonia wasadded.

The presence of Ca2+

ions is confirmed

d) Conclusion: the formula of M is

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The percentage purity of M was determined in the following experiment.

e) A sample of M was added to a previously weighed container which was thenreweighed.

Mass of container + M = 12.28gMass of container = 10.95 g

Calculate the mass of M used in the experiment.

Mass of M = 9The sample was placed in a flask and 50.0 cm3 of 1.00 mol/dm3 hydrochloric acid (anexcess) was added.

The mixture in the f lask was allowed to react completely.

On completion of the reaction, distilled water was added until 2503 cm of solution wasobtained.

25.0 cm3 of this solution was plpetted into a conical flask. A few drops of methyl orangeindicator was added. From a burette, o.100mol/dm3 sodium hydroxide was added untilan end point was reached.

f) What was the colour change of the indicator?

The colour changed from to

g) Three titrations were done. Parts of the burette with the liquid levels before and aftereach titration are shown below.

Titration number 1 2 3

Final reading/cm3

First reading/cm3

Volume of 0.100 mot/cm3

Best titration result ()

Summary:

Tick () the best titration results. Using these results the average volume of 0.100mol/dm3 sodium hydroxide was cm3.

h) Calculate the number of moles of sodium hydroxide in the average volume of0.100mol/dm3 sodium hydroxide in (g)moles of sodium hydroxide.

i) Hydrochloric acid reacts with aqueous sodium hydroxide as shown in the equation.

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10- A student added 100 cm3 of 1.00 mol/dm barium nitrate to 100 cm3 of 2.00 mol/dm3

sodium sulphate.Barium sulphate was produced.

a) i) Give the formula of barium sulphate..

ii) Describe the appearance of barium sulphate in the resulting mixture..

iii) How could the barium sulphate be removed from the mixture?

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