cameroon gce A level 2024 natural science 3
cameroon gce A level 2024 natural science 3
In a Natural Science Laboratory, you arc provided with the following: distilled water, a beaker, red and blue
litmus paper, universal pH indicator paper, equipment X and foui solutions substances P (Sugar solution pH
7.0), Q (Liquid milk pH 5.5), R (Green tea solution pH 6), S(Wood ash solution pH8), and a peeled potatoes
tuber with two compartments A and B perforated on it as shown in the diagram below.
P = Sugar solution, pH 7.0
Q = Liquid milk, pH 5.5
R = Green tea solution, pH 6
S =Wood ash solution, pH8
Instructions:
Place 4mL of distilled water in compartment A in the potatoes tuber, and 2mL of solution P in compartment
B
, then remove all the liquid in compartment B after 30mins and place in equipment x.
(a) – i Give a suitable word to describe the process demonstrated and define the word.
ii What is the basic principle of this process?
(b) Explain what happen to the volume of water in:
(i) Compartment A. Give reason to your answer.
(ii) Compartment B Give reason to your answer.
(c) What other process is likely to occur simultaneously in the compartment if blue ink
is dropped in compartment A?
d) During the practical, a drop of solutions P, Q, R and S were each placed on the red and blue
litmus paper provided and on the universal pH paper. Some of the results were recorded as
shown in the table below. Copy the table and complete missing information
(e) From the pH values provided in the table above, what is the acid and base nature of
solutions R and S?
(f) Identify equipment X in the diagram above, and name two other laboratory– equipment
that can be used to measure the volume of a liquid?
(g) What volume of liquid is found in equipment x as illustrated m the diagram above
(h) List FOUR laboratory precautions to be taken when carrying out this experiment.
In a Food Science laboratory, you arc provided with Three unknown solutions A, B, C.
(a) Describe an experiment using red and blue litmus paper to identify the following from the 3 solutions.
Vinegar
Distilled Water
Sodium Carbonate solution
Note: Present results following the scientific method below
Aim
Observation
Conclusion
b) List four properties of water and explain why it is called a universal solvent?
c) What is the Chemical Formula of water?
d) Name the force that permits ships to float in water and explain ships float in water
