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- A student attempted to prepare a gas using the set-up below. She could not collect any gas(Solved)
A student attempted to prepare a gas using the set-up below. She could not collect any gas
(a) Give two reasons why no gas was collected
(b) Which gas did the student intend to prepare?
Date posted: October 25, 2019. Answers (1)
- Two samples of hard water C and D were boiled. When tested with drops of soap, sample D formed lather easily while C did not:-
(a)...(Solved)
Two samples of hard water C and D were boiled. When tested with drops of soap, sample D formed lather easily while C did not:-
(a) Name the possible salt that caused hardness in sample D
(b) Explain how distillation can remove hardness in sample C
Date posted: October 25, 2019. Answers (1)
- The table shows solubility of potassium chlorate V(Solved)
The table shows solubility of potassium chlorate V
(a) Calculate the mass of solute and solvent in 90g of the saturated solution of the salt at 45oC
(b) A solution of the salt in 100g water contains 63g at 95oC. At what temperature will the solution start forming crystals when cooled
Date posted: October 25, 2019. Answers (1)
- Describe how you would prepare a dry sample of crystals of potassium sulphate starting with 100cm3 of 1M sulphuric (VI) acid.(Solved)
Describe how you would prepare a dry sample of crystals of potassium sulphate starting with 100cm3 of 1M sulphuric (VI) acid.
Date posted: October 25, 2019. Answers (1)
- In an experiment to determine solubility of sodium chloride, 10.0 cm3 of a saturated solution of sodium chloride weighing 10.70g were placed in a volumetric...(Solved)
In an experiment to determine solubility of sodium chloride, 10.0 cm3 of a saturated solution of sodium chloride weighing 10.70g were placed in a volumetric flask and diluted to a total of 500cm3. 25.0 cm3 of the diluted solution of sodium chloride reacted completely with 24.0 cm3 of 0.1M silver nitrate solution.
I. Calculate;
(i) Moles of silver nitrate in 24.0 cm3 of solution.
(ii) Moles of NaCl in 25.0 cm3 of solution.
(iii) Moles of NaCl in 500 cm3 of solution.
(iv) Mass of NaCl in 10.0 cm3 of saturated sodium chloride (Na = 23, Cl = 35.5)
(v) Mass of water in 10.0cm3 of saturated solution.
(vi) The solubility of NaCl in g/100g of waters.
Date posted: October 25, 2019. Answers (1)
- Calculate the solubility of salt given that 15g of the salt can saturate 25cm3 of water(Solved)
Calculate the solubility of salt given that 15g of the salt can saturate 25cm3 of water
Date posted: October 25, 2019. Answers (1)
- Below is a table showing the solubilities of salts Q and R at different temperatures.(Solved)
Below is a table showing the solubilities of salts Q and R at different temperatures.
(a) Define the term “Solubility of salt”
(b) If both salts Q and R are present in 100cm3 of saturated solution at 50oC, what will be the total mass of crystals formed if the solution was cooled to 20oC?
Date posted: October 25, 2019. Answers (1)
- The solubility of Iron (II) Sulphate crystals are 22oC is 15.65g per 100g of water. Calculate the mass of iron(II) sulphate crystals in 45g of...(Solved)
The solubility of Iron (II) Sulphate crystals at 22oC is 15.65g per 100g of water. Calculate the mass of iron(II) sulphate crystals in 45g of saturated solution at the same temperature
Date posted: October 25, 2019. Answers (1)
- A sample of water from a village in Trans Mara East District was divided into equal portions
and each mixed with equal volume of soap solution....(Solved)
A sample of water from a village in Trans Mara East District was divided into equal portions
and each mixed with equal volume of soap solution. The observations made are tabulated below:
What type of hardness is present in water from the village. Explain
Date posted: October 25, 2019. Answers (1)
- Study the reaction below and answer the questions that follow(Solved)
Study the reaction below and answer the questions that follow
(a) Identify an acid in the above reaction
(b) Explain your answers in (a) above
Date posted: October 25, 2019. Answers (1)
- In an attempt to prepare a gas, Sabulei added concentrated hydrochloric acid to Potassium manganate. The products were then passed through two wash bottles containing...(Solved)
In an attempt to prepare a gas, Sabulei added concentrated hydrochloric acid to Potassium manganate. The products were then passed through two wash bottles containing water and concentrated sulphuric acid
(a) Name the gas prepared
(b) Name the purpose of wash bottle:
(i) Containing water
(ii) Containing concentrated sulphuric acid
Date posted: October 25, 2019. Answers (1)
- The figure below was set by a student to investigate the reaction between chlorine gas and hydrogen gas:(Solved)
The figure below was set by a student to investigate the reaction between chlorine gas and hydrogen gas:
(a) Write an equation for the reaction that took place in the flask
(b) What observation was made in the flask?
(c) What precaution should be taken in carrying out the experiment?
Date posted: October 24, 2019. Answers (1)
- Study the flow diagram below and answer the questions that follow:(Solved)
Study the flow diagram below and answer the questions that follow:
(a) Name gas L
(b) Write a balanced equation for the reaction between hydrochloric acid and manganese
(IV) oxide
(c) Explain what happens to coloured petals when dropped into a solution of M
Date posted: October 24, 2019. Answers (1)
- The following diagram represents a set-up that can be used in the laboratory to prepare and collect a sample of chlorine gas:(Solved)
The following diagram represents a set-up that can be used in the laboratory to prepare and collect a sample of chlorine gas:
Date posted: October 24, 2019. Answers (1)
- In an attempt to prepare Sulphur (IV) Oxide gas, dilute Sulphuric acid was reacted with barium carbonate. The yield of Sulphur dioxide was found to...(Solved)
In an attempt to prepare Sulphur (IV) Oxide gas, dilute Sulphuric acid was reacted with barium carbonate. The yield of Sulphur dioxide was found to be negligible.
Explain
Date posted: October 24, 2019. Answers (1)
- Sulphur (IV) oxide and nitrogen (II) oxide are some of the gases released from internal combustion engines. State how these gases affect the environment(Solved)
Sulphur (IV) oxide and nitrogen (II) oxide are some of the gases released from internal combustion engines. State how these gases affect the environment
Date posted: October 24, 2019. Answers (1)
- The set-up below was used to prepare and collect hydrogen sulphide gas. Study it and answer the questions that follow:-(Solved)
The set-up below was used to prepare and collect hydrogen sulphide gas. Study it and answer the questions that follow:-
(a) Name solid V
(b) Give a reason why warm water is used in the set-up
Date posted: October 24, 2019. Answers (1)
- In the manufacture of Sulphuric (VI) acid by contact process sulphur (IV) oxide is made to react with air to form sulphur (VI) oxide as...(Solved)
In the manufacture of Sulphuric (VI) acid by contact process sulphur (IV) oxide is made to react with air to form sulphur (VI) oxide as shown:-
(i) Name the catalyst in this reaction
(ii) State and explain the effect of the following changes on the yield of sulphur (VI) oxide
I. Increasing the pressure
II. Using a catalyst
(iii) Explain why sulphur (VI) oxide gas is absorbed in concentrated sulphur (VI) acid before dilution
Date posted: October 24, 2019. Answers (1)
- The set-up below was used to prepare dry sample of hydrogen sulphide gas(Solved)
The set-up below was used to prepare dry sample of hydrogen sulphide gas
(a) (i) Complete the diagram to show how the gas was collected
(ii) Identify the following:-
I. Solid H
II. Solid I
(iii) Write an equation for the reaction that occurred in the flask between solid H and dilute Hydrochloric acid
(b) When hydrogen sulphide gas was passed through a solution of Iron (III) chloride, the following
observations were made:-
(i) the colour of the solution changed from reddish-brown to green and
(ii) a yellow solid was deposited
Explain the observation
Date posted: October 24, 2019. Answers (1)
- The diagrams below represent two allotropes of Sulphur. Study them and answer the questions which follow:-(Solved)
The diagrams below represent two allotropes of Sulphur. Study them and answer the questions which follow:-
(i) Name the two allotropes labelled X and Y
(ii) (I) Explain why a piece of burning magnesium continues to burn in a gas jar of Sulphur (IV) Oxide
(II) Explain how one of the products formed in (I) above can be obtained from the mixture
Date posted: October 24, 2019. Answers (1)