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(a) A student was supplied with a colourless liquid suspected to be water
The flow chart below shows the various stages of water treatment. Study it and answer the questions that follow
II Addition of sodium hypochlorite (c) It was confirmed that magnesium sulphate was present in the tap water
Expected Response
(a) The following diagrams show the structures of two allotropes of carbon. Study them and answer the questions that follow
(i) Name allotrope
M N (ii) Give one use of N (iii) Which allotrope conducts electricity? Explain
(b) In an experiment, carbon dioxide gas as passed over heated charcoal and the gas produced collected as shown in the diagram below
(i) Write an equation for the reaction that took place in the combustion tube
(ii) Name another substance that can be used instead of sodium hydroxide (iii) Describe a sample chemical test that can be used to distinguish between carbon dioxide and carbon monoxide (iv) Give one use of carbon monoxide
Expected Response
(a) Give the names of the following compounds
Name the type of bromination reaction that takes place in: (i) and (ii)
(d) The polymerization of tetra flouroathene (C2H4) is similar to that of ethane ( C2H4)
(e) State any two advantages that synthetic polymers have over natural polymers
Expected Response
(a)
(b) A sample of hydrogen chloride gas was dissolved in water to make 250cm3 of solution required 46 cm3 of 11.0M Sodium hydroxide for complete neutralization.
Expected Response
State and explain the function of tartaric acid in baking powder
Expected Response
It reacts with NaHCO3 to form CO2 which causes the dough to rise.
​(a) The grid given below represents part of the periodic table. Study it and answer the questions that follow. (the letters do not represents the actual symbol of the elements)
​(b) Study the information in the table below and answer the questions that follow (the letters do not represent the actual symbol of the substances)
II. By downward displacement of air? (Density of air is 1.29 x 10-3g/cm3 at room temperature.
Expected Response
Related Chemistry Questions and Answers on Chemical Families Form 2 Level
​The flow chart below illustrate the industrial extraction of lead metal. Study it and answer the questions that follow
(a)
(c) State one use of lead other than the making of lead pipes
Expected Response
Related Chemistry Questions and Answers on Metals Form 4 Level
1 (a) The diagram below represents a mercury cell that can be used in the industrial manufacture of sodium hydroxide. Study it and answer the question that follow
Expected Response
In an experiment, ammonia chloride was heated in a test tube. A moist red litmus paper placed at the mouth of the test tube first changed blue then red. Explain these observations
Expected Response
NH4Cl decomposes to form NH3(g) and HCl(g).Ammonia diffuses faster than HCl because its light. Ammonia is basic and thus red litmus paper turns blue while HCl is acid thus blue litmus turns red.
Explain why it is not advisable to leave a Jiko with burning charcoal in a closed room where one is sleeping.
Expected Response
The supply of oxygen in the room will be limited leading to formation of CO which is poisonous.
Hydrogen and fluorine react according to the equation below
Expected Response
When a solid sample of sulphur is heated in a test tube, it changes into a liquid, which flows easily. On further heating, the liquid darkness and does not flow easily. Explain these observations.
Expected Response
Solid sulphur is made of S8 rings. It melts into aliquid of S8 rings, On further heating the rings open up to form long chains of sulphur atoms, which then entangle making it viscous and dark, or sulphur melts into S8 molecules. The molecules join up to form long chain which entangle making it viscous and dark
Study the information in the table below and answer the questions that follow. The letters do not represent the actual symbols of the elements)
Select an element which
Expected Response
Name another gas, which is used together with oxygen in welding
Expected Response
Acet5ylene (ethyne) or Hydrogen
Pentane and ethanol are miscible. Describe how water could be used to separate a mixture of pentane and ethanol
Expected Response
20. Add water to the mixture in a separating funnel. Ethanol dissolves while pentane does not. Allow the mixture to separate in two layers. Open the tap to drain the lower aqueous layer. Distil the water ethanol mixture to get ethanol.
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December 2024
AuthorMaurice Atika is a teacher and a netprenuer. |
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