CHEMISTRY - Form 1 End of Term 1 2019 Examinations

State three differences between luminous and non-luminous flame. (3mks)
The diagram below shows a non–luminous flame of the Bunsen burner

Name the parts of the flame labelled (3mks)
A
B
C

1. What is a drug? (1mk)
2. State two long- term effects of drug abuse (2mks)

Putting off flames after use is one of the safety rules in the laboratory. State three other safety rules. (3 marks)

Name four career opportunities open to a chemist? (4mk)

The diagram below represents a paper chromatogram for three brands of juices suspected to contain banned food colourings?

The results showed the presence of banned food colourings L and M only.
On the same diagram:
1. Circle the spots which show the banned food colouring? (2mks)
2. Show the solvent front (1mk )
The diagram below shows then relationship between the physical state of matter. Study it and answer the questions that follow
1. Identify the following processes (2 mks)
  R
  V
  W
  U
2. Name two substances which can undergo the processes represented by S and I (2mks)

The set up below was used to determine the melting point of naphthalene.
1. State one precaution which should be taken into consideration when carrying out this experiment (1mk)
2. State the use of the following in this experiment
  1. Thermometer (1mk)
  2. Stirrer (1mk)
  3. Boiling water (1mk)
1. The apparatus shown below is commonly used in chemistry laboratory. Give its name and state one use. (2mks)
2. Draw and name any two apparatus for measuring volume (2mks)
In an experiment to separate a mixture of two liquids A and B, a student set up the apparatus as shown below
1. Name the apparatus (1mk)
2. Which liquid is denser (1mk
3. Which other method can be used to separate the two liquids? (1mk)
1. What is a mixture? (1mk)
2. State an example for each of the following categories of mixtures. (3mks)
  1. Solid-Solid
  2. Solid-Liquid
  3. Liquid- Liquid
1. Define a conductor (1mk)
2. Categorise each of the following substances as either conductor or non-conductors of electricity. (2mks)
  1. Aluminium
  2. Rubber eraser
1. State two skills acquired in the study of chemistry (2mk)
2. Give two industries where the knowledge of chemistry is applied. (2mks)
Study the diagram below and answer the questions that follow
1. State the condition under which the flame above is produced (1mk)
2. A wooden splint was introduced into the flame as shown in the diagram. Draw a sketch showing the observation made on the splint and explain the observation made (3mk)
The following symbols had been put on containers which certain chemicals identify the symbol and explain its meaning. (6marks)
A student wanted to extract oil from cashew nuts. He first crushed the nuts then added propanone a little at a time while still crushing. He allowed it to settle, decanted the resulting solution then exposed it to sunlight for propanone to evaporate.
1. Why was it necessary to crush the cashew nuts before adding propanone ( 1mk)
2. Why was propanone preferred to water in the experiment (1mk)
3. Name the method of extraction described above. (1mk)
Study the diagram below and answer the questions that follow. It shows the heating curve for naphthalene.
1. Explain the shape of the graph at region BC (2mk)
2. State whether the naphthalene used was pure or impure. Give a reason for your answer (2mk)
3. Explain the behaviour of naphthalene particles at region AB (2mk)
1. Differentiate between a temporary physical change and a temporary chemical change (1mk
2. State two observations made when copper (ii) sulphate crystals are heated in a test tube (2mk)
3. Is heating of cobalt (ii) chloride crystals a chemical change or a physical change (1mk)
A student set up the following experiment to carry out fractional distillation
1. Name the apparatus labelled
  1. P (1mk)
  2. Q (1mk)
2. Write down one error that was made in setting up the apparatus. (1mk)
3. What is the role of glass beads in fractional distillation (1mk)
4. What other apparatus would you use to improve the role played by the cold water?
What do you understand by the term over the counter (OTC) drugs (2mk)
State why the following laboratory rules should be followed
1. Never wear loose clothing in the laboratory (1mk)
2. When heating a substance in a test tube or boiling tube never let the open end face you or your neighbour (1mk)
1. Define matter (1mk)
2. List the states of matter (1mk)
The diagram below shows a Bunsen burner.
1. Name the parts labelled
  E
  F
  G
2. What is the role of the part labelled F? (1mk)