(a) To cool/condense vapour.
(b) Water.
(c) Blue solid changes to white solid.
maurice.mutuku answered the question on October 11, 2019 at 09:20
- A form 1 student carried out the separation as shown in the set-up below:-(Solved)
A form 1 student carried out the separation as shown in the set-up below:-
(i) Identify the method above.
(ii) Give one of its disadvantages
(iii) Name a mixture which can be separated by the set-up above
Date posted: October 11, 2019. Answers (1)
- Cooking oils comprise of a mixture of compounds which have a boiling point range
of 23oC to 27oC.
(i) What evidence is then to support the statement...(Solved)
Cooking oils comprise of a mixture of compounds which have a boiling point range
of 23oC to 27oC.
(i) What evidence is there to support the statement that cooking oil is a mixture?
(ii)Name another experimental technique that could be used to confirm your answer in part (i) above
Date posted: October 11, 2019. Answers (1)
- Without using any laboratory chemical, describe a simple laboratory experiment to distinguish between calcium hydrogen carbonate and sodium hydrogen carbonate.(Solved)
Without using any laboratory chemical, describe a simple laboratory experiment to distinguish between calcium hydrogen carbonate and sodium hydrogen carbonate.
Date posted: October 11, 2019. Answers (1)
- The two elements P and R were separately burned in air, the products gave the results recorded in the table below:(Solved)
The two elements P and R were separately burned in air, the products gave the results recorded in the table below:
(a) Suggest the identity of element R.
(b) Describe how the nature of the solutions of the of the oxides were determined
Date posted: October 11, 2019. Answers (1)
- It is advisable to set a Bunsen burner to luminous flame prior to an experiment.
Explain(Solved)
It is advisable to set a Bunsen burner to luminous flame prior to an experiment.
Explain
Date posted: October 11, 2019. Answers (1)
- The diagram below shows the heating curve of a pure substance. Study it and answer the
questions that follow:(Solved)
The diagram below shows the heating curve of a pure substance. Study it and answer the
questions that follow:
(a) What physical changes are taking place at points X and Z?
(b)Explain what happens to the melting point of sodium chloride added to this substance
Date posted: October 11, 2019. Answers (1)
- Study the information in the table below and answer questions that follow.
(Letters given are not real symbols)(Solved)
Study the information in the table below and answer questions that follow.
(Letters given are not real symbols)
Explain why the ionic radius of :-
(a) B+ is greater than that of A+
(b) C2+ is smaller than the of A+
Date posted: October 11, 2019. Answers (1)
- The diagram below shows some parts of a Bunsen burner(Solved)
The diagram below shows some parts of a Bunsen burner
Explain how the parts labelled T and U are suited to their functions
Date posted: October 11, 2019. Answers (1)
- The diagrams below are some common laboratory apparatus. Name each apparatus and state its use(Solved)
The diagrams below are some common laboratory apparatus. Name each apparatus and state its use
Date posted: October 11, 2019. Answers (1)
- A mixture of hexane and water was shaken and left to separate as shown in the diagram below:(Solved)
A mixture of hexane and water was shaken and left to separate as shown in the diagram below:
State the identity of;
(i) P
(ii) W
Date posted: October 11, 2019. Answers (1)
- The diagram below shows three methods for collecting gases in the laboratory(Solved)
The diagram below shows three methods for collecting gases in the laboratory
(a) Name the methods A and B
(b) From the methods above, identify one that is suitable for collecting sulphur (IV) oxide.
Explain
Date posted: October 11, 2019. Answers (1)
- Give two drugs that are commonly abused by the youth.(Solved)
Give two drugs that are commonly abused by the youth.
Date posted: October 11, 2019. Answers (1)
- What is a drug?(Solved)
What is a drug?
Date posted: October 11, 2019. Answers (1)
- Draw a labelled diagram of a non-luminous flame(Solved)
Draw a labelled diagram of a non-luminous flame
Date posted: October 11, 2019. Answers (1)
- Wooden splints F and G were placed in different zones of a Bunsen burner flame.
The diagram below gives the observations that were made(Solved)
Wooden splints F and G were placed in different zones of a Bunsen burner flame.
The diagram below gives the observations that were made
(a) Explain the difference between F and G
(b) Name the type of flame that was used in the above experiment
Date posted: October 11, 2019. Answers (1)
- Calculate the number of Al3+ ions released when 30cm3 of 0.1M of Aluminum Sulphate is dissolved in water (L= 6.024 x 1023)(Solved)
Date posted: October 1, 2019. Answers (1)
- The set-up below shows the products formed when solid lead (ii) nitrate is heated.(Solved)
The set-up below shows the products formed when solid lead (ii) nitrate is heated.
a) Identify:
(i) Liquid X
(ii) Gas Y
b) When lead (ii) Nitrate crystals are heated, they decrepitate and decompose, what is meant by the term decrepitating?
Date posted: October 1, 2019. Answers (1)
- The following diagram shows the effect of electric current on lead (II) Chloride(Solved)
The following diagram shows the effect of electric current on lead (II) Chloride.
a) When the circuit was completed no current flowed. Explain why.
b) When lead (II) Chloride was heated to about 300 degrees C, it melted and there was light on the bulb. State and explain the observation made at the anode.
Date posted: October 1, 2019. Answers (1)
- Explain using chemical means how you would differentiate between carbon (II) oxide and carbon (IV) oxide.(Solved)
Explain using chemical means how you would differentiate between carbon (II) oxide and carbon (IV) oxide.
Date posted: October 1, 2019. Answers (1)
- Study the table below and answer the questions that follow.(Solved)
Study the table below and answer the questions that follow.
a) Define the term ‘ionization energy’
b) Explain the trend in the ionization energy from element K to T
c) Compare the trend in the melting and boiling points of elements K and T.
Date posted: October 1, 2019. Answers (1)