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a) You are provided with solid L. Use it to carry out the tests below and record your results in the table provided.

TEST

OBSERVATION

INFERENCES

a) Transfer all solid L into a boiling tube. Add 10cm³ of 1M HNO₃ and shake Dip a glass rod into calcium Hydroxide solution and place it at the mouth of the boiling tube.

1 mk

½ mk

b) To about 2 cm³ of the solution in a test tube add 3 drops of lead II Nitrate solution and warm

1 mk

½ mk

c) To about 2 cm³ of the solution in another test tube add 2M sodium Hydroxide solution drop wise till in excess

½ mk

d) To about 2 cm³ of solution in another test tube dip a clean metallic spatula in the solution and place it on a burner flame.

½ mk

b) You are provided with solid Q, you are required to:

i) Carry out the tests described below on solid Q

ii) Record your observations and inference accordingly

iii) Test any gases provided.

Procedure:

i) Place a spatula full of solid Q in a boiling tube

ii) Add about 15 cm³ of distilled water and shake

iii) Divide the resulting solution into four portions

iv) Use a universal indicator paper to test portion one of the solution

Observation

Inferences

(1/2 mark)

v) Add a spatula full of sodium carbonate to the second portion.

Observation

Inferences

(1/2 mark)

vi) Add three drops of acidified Potassium Manganate (vii) solution to the third portion.

Observation

Inferences

(1/2 mark)

You are provided with solid P. Carry out the tests below. Identify any gas (es) produced. Record your observations and inferences in the spaces provided.

(a) Place about half of the solid P in a dry test tube. Heat the solid gently.

Observation

Inferences

(1 mark)

(b) Dissolve the remaining portion of solid P in 10cm³ of distilled water in a boiling tube. Divide the solution into four portions To the first portion, add sodium hydroxide dropwise till in excess.

Observation

Inferences

(1 mark)

(c ) To the second portion, add 3 drops of ammonia solution followed by 1cm³ of hydrogen peroxide

Observation

Inferences

(1 mark)

(d) To the third portion, add about 1cm³ of nitric acid solution

Observation

Inferences

(1 mark)

(e) To the fourth portion, add 3 drops of barium nitrate solution.

Observation

Inferences

(1 mark)

You are provided with solid Q. Carry out the test below. Write your observations and inferences in the spaces provided.

(a) Using a spatula place about one third of solid Q in a clean dry test-tube and heat it strongly.

Observation

Inferences

(1 mark)

(b) Place the remaining solid Q in a boiling tube. Add about 10cm³ of distilled water. Shake the mixture thoroughly for about one minute. Filter and divide the filtrate into four portions.

Observation

Inferences

(1 mark)

(c) To the first portion, add 2 drops of phenolphthalein indicator

Observation

Inferences

(1/2 mark)

(1 mark)

(d) To the second portion, add 2cm³ of dilute hydrochloric acid.

Observation

Inferences

(1/2 mark)

(1 mark)

(e) To the third portion, add 5cm³ of aqueous sodium sulphate

Observation

Inferences

(1 mark)

(f) To the fourth portion, add dilute sodium hydroxide dropwise until in excess.

Observation

Inferences

(1 mark)

You are provided with:-

- Solution A containing 4.0g sodium hydroxide per litre solution.

- Aqueous hydrochloric acid solution.

- Calcium hydroxide

– Solid C.

You are required to standardize hydrochloric acid solution B using solution A and hence determine the solubility of solid C in 100g of water at room temperature.

PROCEDURE I

- Place all the solid C into a clean conical flask.

- Measure accurately 100cm³ of distilled water using a measuring cylinder and add it to solid C.

- Shake thoroughly and leave it to stand for 12 minutes.

- Fill the burette with solution B.

- Pipette 25cm³ of solution A into a clean conical flask.

- Add 3 drops of phenolpthalein indicator and titrate with solution B.

- Record the results in the table below.

- Repeat the experiment to obtain three consistent readings

Experiment	I	II	III
Final burette reading (cm³)
Initial burette reading (cm³)
Volume of solution B used (cm³)

(a) Determine the average volume of solution B used. (1 mark)

(b) Determine the molarity of solution A. ( 1 mark)

(c) Determine the molarity of solution B. (2 marks)

PROCEDURE II

-Filter the saturated solution of the mixture C and water into a clean conical flask and label this solution C.

-Using pipette and filler, transfer 25cm³ of the filtrate into a conical flask and titrate with hydrochloric acid solution B using methyl orange indicator.

-Record the results in the table below.

-Repeat the titration to obtain consistent readings

Experiment	I	II	III
Final burette reading (cm³)
Initial burette reading (cm³)
Volume of solution B used (cm³)

(a) Determine the average volume of solution B used. ( 1 mark)

(b) Determine the number of moles of solution B used. ( 1mark)

(c ) Calculate the number of moles of C in 25cm³ of the filtrate. ( 2 marks )

(d) Calculate the number of moles of solid C in 100cm³ of solution . ( 1 mark)

(e) Calculate the solubility of solid C per 100g of water ( Ca = 40.0, O = 16.0, H = 1.0) Density of water = 1 g/cm³ (2 marks)

You are provided with the following apparatus.

Lit candle
One biconvex lens mounted on a lens stand
Small amount of plasticine
One metre rule
One white screen

Procedure:

a) Arrange the lit candle and the white screen on the bench at a distance of 100 cm from each other. Mount the metre rule on the bench as shown so that its zero mark coinside with the point of the lit candle and the 100 cm mark coinside with the point of the screen.

b) Place the lens between the screen and the lit candles at a point near the candle. Move the lens systems together with it holder towards the screen until you obtain a sharp magnified inverted image of the flame of the lit candle on the screen.

Record distance U₁ between the lens and the lit candle.

U₁ = ................................................................................................................................................cm ( ½ mk)

c) Move the lens system further towards the screen until you obtain another position where sharp diminished inverted image of the flame is formed on the screen.

Record the new distance u₂ of the lens

u₂ .............................................( ½ mk)

d) Determine displacement d of the lens system (1mk)

...........................................................................................................................................................

e) Determine the constant given that and (1mk)

...........................................................................................................................................................

You are provided with the following apparatus:

One voltmeter ( 0 – 3V or ) -5v )
One ammeter ( 0 – 1A)
Six connecting wires, each at least 30 cm long. Three of which are connected to crocodile clips at one end.
One new dry cell placed in a cell holder.
One metre long nichrome wire mounted on a table and labeled MN

Procedure:

a) Set up the circuit shown below.

N/B: The arrows in the diagram indicate crocodile clips. The crocodile clip next to the cell should be used as a switch.Connect the crocodile clip next to the cell and disconnect the one at P.

Record the voltmeter reading V₀.

V₀ = ___________________________ (1mk)

b) Connect the crocodile clip at p, at a distance L = 50 cm from m.

Record the reading of both the ammeter and the voltmeter when the crocodile clip next to the cell is connected.

Reading of ammeter I = ........................................................................A ( ½ mk)

Reading of voltmeter V = ........................................................................V ( ½ mk)

c) Determine the quantity , given the following relationship. (3mks)

...........................................................................................................................................................

You are provided with the following apparatus

-Two metre rules

-One half metre rule

-Two pieces of cotton thread.

-Two heavy stands and two clamps

-One stop watch.

Procedure:

a) Set up the apparatus as shown in the figure below.

N/B:- Ensure the loops on the upper and lower metre rule are loose to enable easy sliding of the threads along the rules. Also the separation between the two rules must be 20cm throughout the experiment.

b) Adjust the position of the threads such that one is on the 10 cm mark and the other on the 90 cm. Mark on the lower metre rule. i.e d = 80 cm.

N/B: Maintain the threads vertical by making same adjustment on the upper metre rule.

Displace one end of the lower metre rule. Slightly on a horizontal plane so that when released it oscillated about a vertical axis as shown by the arrows In the figure. Measure the time for 20 Oscillations and record in the table below.

c) Repeat the procedure in (b) for other values of d shown in the table below (Set the values of d by adjusting the positions of the loops in steps of 5cm on both sides)

Complete the table

(10mks)

d) Plot a graph of T²( y – axis) against 1/d². (5mks)

e) i) Determine the slope of your graph. (3mks)

...........................................................................................................................................................

ii) Given that where K is a constant; determine the value of k. (2mks)

...........................................................................................................................................................

You are provided with the following apparatus:

50 ml measuring cylinder
One 50g hooked mass.
50 cm piece of thread
Some water in a beaker

Procedure:

(a) Pour exactly 20cm³ of water into the measuring cylinder

(b) Tie one end of the thread provided to the hooked mass using the thread lower the 50g mass carefully and gently into the water contained in the measuring cylinder. Record the new level V₁ of water in the measuring cylinder.

V1 = _________________________________cm³ (1mk)

(c) Detouch the thread from the mass at a point near the hook. Wind five close turns round the mass. Place an ink mark at the beginning of the first turn and at the end of the fifth turn. Unwind the thread and determine length L between the two ink marks using the half metre rule.

L = _________________________________mm (1mk)

(d) Determine the quantity K defined by: (1mk)

...........................................................................................................................................................

e) Find the quantity Q defined by: 2mks

...........................................................................................................................................................

You are provided with the following apparatus:

Rectangular glass block
Soft board
Five sheets of plain papers
Four optical pins.
A pair of compasses, a protractor and a set square
Half metre rule.
Four office pins

Procedure:

(a) Using the office pins provided mount one sheet of plain paper on the soft board. Place the rectangular glass block on the plain paper and trace around it using a pencil.

(b) Remove the block, draw a normal at a point O and draw a line making an angle of 150 with the normal to represent incident ray as shown in the diagram below.

(c) Stick two optical pins P and Q along the incident ray and replace the glass block. While closing one eye, look through the glass block from the opposite side and insert two other pins R and S exactly in line with the images of P and Q.

(d) Remove the glass block and join SR to the outline of block. Hence obtain the refracted ray inside the glass block as shown in the diagram.

(e) With O as the centre, Draw a circle of radius 5 cm to cut both the incident ray and the refracted ray at M and L respectively.

f)Using a set square, draw the perpendiculars LY and MN. Measure LY and MN in millimeters and record your value in the table below.

Angle of incidendence i	15	3	45	60	75
LY (mm)
MN (mm)

g) Repeat the above steps for other angles of incidence shown in the table above.

h) Plot a graph of LY ( y – axis) against MN. (5mks)

(i) Calculate the slope,, of your graph. (2mks)

...........................................................................................................................................................

j) Determine the quantity defined by = Sin -1 (2mks)

...........................................................................................................................................................

N/B: Plain papers containing your drawing should be submitted together with the question paper to the invigilator.

You are provided with the following;

A retort stand, boss and clamp.
Test tube
Piece of duplicating paper
A thermometer
A large beaker containing some water
A tripod stand and wire gauze
A cardboard with a hole in the middle
A burner
A rubber band
A stop band
A stop watch

Proceed as follows;

(a) Set up the apparatus as shown below.

(b) Heat the water in the beaker provided and leave it to boil

(c) Wrap the given piece of duplicating paper round the bulb of the thermometer. Use rubber band to hold the paper in place.

(d) Place the thermometer inside in the dry test tube.

(e) Place the test tube in the water as shown in the diagram above. Make sure that the water does not enter the test tube. Leave the test tube in the boiling water until the thermometer indicates a steady temperature.

(f) Remove the thermometer and immediately start the stop watch.

(g) While holding the thermometer in air record the readings of the thermometer T₁ at intervals of 30seconds for 10 minutes.

Time in minutes	0	0.5	1.0	1.5	2.0	2.5	3.0	3.5	4.0	4.5	5.0	5.5
T₁ (⁰c)
T₂(⁰c)

Time in Minutes	6.0	6.5	7.0	8.0	8.5	9.0	9.5	10.0
T₁ (^oC)
T₂(^oC)

(10mrks)

(h) Place the wrapped thermometer directly into boiling water. Leave the thermometer in the boiling water until it indicates a steady temperature.

(i) Repeat procedure (f) and (g) and record the reading T₂ of the thermometer in the table at half minute intervals for 5minutes.

(j) Using the same axes on the grid provided, plot a graph of temperature (y-axis) against time for result obtained in (g) and (i) (label the graph T₁ and T₂)

(k) (8mrks)

(i) From the graphs determine;

I) For each graph the time for temperature to fall from 60⁰C to 40⁰C. (1mrk)

.........................................................................................................................................

II) Find the ratio of the two times in k (i) above (1mrk)

.........................................................................................................................................

1/d² ( m^-2)

Time for 20 Osc. (s)

Period T (s)