FORM TWO PRE- MOCK EXAMINATIONS
GOLDEN SECONDARY SCHOOL – EXTERNAL EXAMINATION
- This paper consists of sections A, B and C.
- Answer all questions in all questions.
- All writing should be in blue or black ink except diagram which must be in pencil.
- All communication devices are not allowed in the examination room.
- Non programmable calculators are allowed in the examination room.
- The following constant may be applied: R.A.M; C = 12, H = 1, O =16, S = 32, Na = 23, Ca =40
SECTION A (10 Marks)
- For each of the items (i) – (x) choose the correct answer from the given alternatives and write its letter in the box provided.
- The part of Bunsen burner that controls the amount of air coming in is called:
- Air hole
- A ____________ is a container which is made of porcelain and in which substances can be heated to very high temperature.
- Wire gauze
- Tripod stand
- Boiling tube
- Which of the following is nota product produced by the use of chemistry in agriculture?
- Weed killers
- Canned food
- Animal vaccines
- Which of the following apparatuses is used for scooping chemicals?
- A pair of tongs
- Test tube holder
- Filter funnel
- An element X with atomic number 16, belongs to:
- Period 3, group III, valency of 2
- Period 3, group VI, valencyof 2
- Period 3, group VI, valency of 6
- Period 6, group VI, valency of 6
- Which of the following is a sequential method of separating mixture of salt and sand?
- Evaporation, filtration and decantation.
- Decantation, evaporation and filtration.
- Sedimentation, evaporation and filtration.
- Decantation, filtration and evaporation.
- what is the oxidation state of chlorine in KClO3
- __________ is the blockage of the upper part of the airway by food or other objects.
- If somebody has the signs of poisoning such as pain, difficulty in breathing, diarrhoea, abdominal cramps or vomiting, we should not:
- Call for medical assistance
- Find out what caused poisoning as it is not important.
- Force him/her to vomit if the poison has been swallowed and it is corrosive.
- Apply ointment if the poison is on the skin.
- Which one comes right after the step 3 (experimentation and observation).
- Formulation of hypothesis
- Data interpretation
- Data collection
- Problem identification
SECTION B (Marks 10)
- You are provided with a two LIST A and B. Choose a word(s) form LIST B which matches the statement or phrase in LIST A and write its letter in the table provided.
SECTION C (Marks 80)
- (a) Write the symbols of the elements below.
- Silver: ________________ (ii) Chromium: _____________
(iii) Calcium: ______________ (iv) Mercury: _______________
(b) Write the IUPAC names for each of the following compound:
- N2 O4__________________________
- Fe2O3 __________________________
- CuO __________________________
- PbO2 __________________________
(c) Explain three points on the importance of changing one state of matter to another.
- Study the periodic Table below:
II III IV V VI VII
Use the letters shown in the Periodic Table above to indicate:
- Elements with zero valency._______________________________________
- The lightest atom.___________________________
- The alkaline earth metal.______________________
- An element with an electronic configuration of 2:8:1._________________________
- Give the names of the elements represented by the mentioned letters A,B,C,D and J
- Write the electronic configuration of J2+. ___________________________________
- (a) In an experiment, two iron nails A and B were used whereby painting was applied on nail A. The two nails were placed in a moist environment and after one month the weight of each nail was determined. Which of the two nails would be heavier? Give reason. ___________________________________________________________________________________
(b) State the method which will be used to protect each of the following from rusting.
(i) Covering iron sheets with a layer of most reactive metals. _____________________________
(ii) Bicycle chain. ___________________________________
(c) Find the oxidation number of the underlined elements in the following:
- (a) (i) Why may a flame produced by a “spirit lamp” not be good for heating in the laboratory? Give
- Name the type of flame produced by a spirit lamp. _______________________________________
(b) By using the locally available materials in your school, state how the fire can be extinguished in the following situations:
(i) Kerosene spilled on the floor catches fire._____________________________________________
- Friend’s clothes catch fire which gets out of her control._________________________________
(c) State four characteristics of a good fuel
- (a) Which method would you use to separate each of the following mixtures?
- Water mixed with kerosene
- Iron powder mixed with sand.
- Ammonium chloride crystals mixed with sodium chloride crystals
- Water mixed with alcohol.
(b) Name one function for each of the following laboratory apparatus:
- Kipp’s apparatus._________________________________________________________________
- Liebig condenser. _________________________________________________________________
- (a) Draw a well labelled diagram of preparation hydrogen gas.
(b) Briefly explain how hydrogen gas is tested in the laboratory.
(c) State any three uses of hydrogen gas.
- (a) What is air?
(b) Mention all the components of air with their percentage composition:
(c)Give four reasons why air is said to be a mixture and not a compound.
- (a) Calculate the percentage composition of the underlined elements in the following compounds:
(b) A compound M is composed of 52.2% carbon, 13% hydrogen and the rest is oxygen. If the molecular
of M is 138, calculate:
- The empirical formula
- The molecular formula