Search
Free School Management System
Free School Management System for Kenya

Free School Management System

Learn More

KCSE CLUSTER TESTS 26

Chemistry Paper 2

Answer all the questions in the spaces provided.
1.

A form one teacher cut small pieces of sodium and performed different experiments. In each of the experiments below, state the observations and write an equation of the reaction. I. A piece of sodium metal is burnt in excess air.

Observation (1mk)

___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________

Equation (1mk)

___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________

II. Product in (I)above is added to water.

Observation (1mk)

___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________

Equation (1mk)

___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________

III. Heated sodium is lowered into a gas jar of chlorine.

Observation (1mk)

___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________

Equation (1mk)

___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________

IV. A small piece of sodium is put in cold water in a beaker and resulting solution is tested with litmus paper. Observation (1mk) ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________

Equation (1mk)

___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________

b) Define the term ionization energy. (1mk)

___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________

c) Study the following ionization energy values and answer the questions that follow.

i) What do the values of energies of ionization suggest about the

I. first electron removed from a sodium atom. ( 1 ½ mk)

___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________

II. First two electrons removed from a magnesium atom.( 1½mk) ___________________________________________________________________________ _______________

___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________

ii) Calculate the energy change in the process ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________

13 marks

2.

a) Study the information in the table below and answer the questions that follow.

i) Write the general formula of the Hydrocarbons in the table (1mk) ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________

ii) Predict the relative mass of the Hydrocarbon with 5 carbon atoms. (1mk) ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________

iii) Determine the molecular formula of the Hydrocarbon in (ii) above and draw the structural formula. Molecular formula (1mk) ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________

Structural formula (1mk) ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________

2 (b) The scheme below shows some reactions starting with Propanol. Study it and answer the questions that follow.

iii) Name the type of reaction, reagent and conditions in the reactions in step I and step IV.

iv) Name two chemical tests that can be used to differentiate propanol from propanoic acid. ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________

13 marks

3.

Study the scheme below and answer the questions that follow.

a) Identify X and Y and give their sources.

X__________________________________________________________________________ _(1mk) Source_____________________________________________________________________ ___ ___________________________________________________________________________ ___ Y__________________________________________________________________________ _____ Source_____________________________________________________________________ ____ ___________________________________________________________________________ ___(1mk)
b) Identify the catalyst used in step I (1mk)

c) Name the substances (2mks) A_______________________________________________________

B_______________________________________________________

C_______________________________________________________

D_______________________________________________________

d) Write chemical equations that shows

i) The formation of substance C (2mks) ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________

ii) The reaction between substance C and copper metal. (2mks) ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________

e) Describe a chemical test for gas E. (1mk) ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________

f) i) State one economic use of substance (1mk) F__________________________________________________________________________ _______________ ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________

ii) Name the optimum conditions for the production of ammonia gas. (1mk) ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________

12 marks

4.

i) Write a balanced equation to show the reaction that takes place when ethanol burns. (1mk)

___________________________________________________________________________ ______________ ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________
ii) Calculate the heat energy.

I. absorbed by the water. (1mk) ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________

II. given out when one mole of ethanol was burned completely. (2mks) ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________

b) Use the information in the energy cycle diagram below to answer the questions that follow.

___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________

c) Using the information and answer in b (ii) above draw the energy level diagram for dissolving magnesium chloride. ___________________________________________________________________________ _______________ ___________________________________________________________________________ _______________

11 marks

5.

The diagram below shows some reactions starting with Lead(II) nitrate solid. Study it and answer the questions that follow.

____________________________________________________________________________________ _(1mk)

ii) Identify

I. Reagent K. (1mk) ____________________________________________________________________________________ ______ ____________________________________________________________________________________ ______

II. Gas Q

________________________________________________________________________________(1m

k)

III. Acidic products S and R. (2mks) ____________________________________________________________________________________ ______ ____________________________________________________________________________________ ______

iii) Write

I. The formula of the complex ion formed in step 3. (1mk) ____________________________________________________________________________________ ____________

II. The equation for the reaction in step 5. (1mk) ____________________________________________________________________________________ ____________ ____________________________________________________________________________________ ____________

b) i) The reaction between lead (II) nitrate and concentrated sulphuric acid starts but stops immediately. Explain with the help of an equation. (2mks)

____________________________________________________________________________________ ____________

ii) Name one reagent that can be reacted with concentrated sulphuric acid to produce nitric

(v) acid. (1mk) ____________________________________________________________________________________ ____________ ____________________________________________________________________________________ ____________

c) Write the formula of the ion formed in each of the reactions described below.

i) Excess ammonia is added to solution containing copper (II) ions. (1mk) ____________________________________________________________________________________ ____________ ____________________________________________________________________________________ ____________

ii) Excess sodium hydroxide solution is added to a solution containing aluminium ions. (1mk) ______________________________________________________________________________ ________________ ____________________________________________________________________________________ ____________ ____________________________________________________________________________________ ____________

12 marks

6.

The diagram below is the down cell for the extraction of sodium metal. Use it to answer the questions that follow.

a) In which state is sodium chloride and how is it maintained in the state. (2mks)
____________________________________________________________________________________ ____________ ____________________________________________________________________________________ ____________ ____________________________________________________________________________________ ____________

b) Name solid V and state its use.

Name________________________________________________________( ½ mk) Use____________________________________________________________( ½ mk)

c) Give a reason why the anode is made of graphite and not steel. (1mk)
____________________________________________________________________________________ ____________ ____________________________________________________________________________________ ____________ ____________________________________________________________________________________ ____________

d) Write equations for reactions that take place at

Anode_____________________________________________________________( ½ mk) Cathode____________________________________________________________( ½ mk)

e) State the main impurity in the sodium collected and state how it is removed.

Impurity_________________________________________________________1mk)

How

removed__________________________________________________________________________ _ _________________________________________________________________________________ ________(1mk)

g) State any two uses of sodium metal. (2mks) ____________________________________________________________________________________ ____________ ____________________________________________________________________________________ ____________

10 marks

7.

a) The set up below represents the arrangement used to prepare substance S by passing a stream of dry hydrogen chloride gas over heated iron wool.

i) Correct the mistake in the set up above (1mk) _________________________________________________________________________________ ________________ _________________________________________________________________________________ ________________

ii) Give the chemical equations for the reaction.

I. that involves formation of substance

S___________________________________________________________________________________ (1mk)

II. at point X__________________________________________________________________________ (1mk) ____________________________________________________________________________________

iii) What precautions would you take when carrying out this experiment. Give reasons precaution I_________________________________________________________________________( ½ mk) Reason______________________________________________________________________________ ______ ( ½ mk)

Precaution 2_____________________________________________________________________________ ____________________________________________________________________________________ ________ ( ½ mk)

Reason______________________________________________________________________________ ____________________________________________________________________________________ ________________________( ½ mk)

b) 300cm3 of hydrogen chloride gas were passed over 7.0g of heated iron wool until there was no further change. The reaction vessel then was allowed to cool to room temperature. i) Determine the mass of iron that remained at the end of the experiment.(Molar gas volume at r.t.p=24000cm3, Fe=56) ____________________________________________________________________________________ _________________ ____________________________________________________________________________________ _________________ ____________________________________________________________________________________ _________________ ____________________________________________________________________________________ _________________ ____________________________________________________________________________________ _________________

ii) Determine the volume of 2M sulphuric acid that would be required to react with excess iron that remained in the above experiment, b(i) above. ____________________________________________________________________________________ _________________ ____________________________________________________________________________________ _________________ ____________________________________________________________________________________ _________________ ____________________________________________________________________________________ _________________ ____________________________________________________________________________________ _________________ ____________________________________________________________________________________ _________________

9 marks

Back Top