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- The products of a burning candle were passed through a tube containing calcium oxide as shown in the diagram below.(Solved)
The products of a burning candle were passed through a tube containing calcium oxide as shown in the diagram below.
(a) Write two chemical equations for the reactions that took place in tube P.
(b) Name two gases that came out through tube R.
Date posted: March 26, 2019. Answers (1)
- Excess Carbon (II) Oxide was passed over a heated sample of an oxide of iron as shown in the diagram below. Study the diagram and...(Solved)
Excess Carbon (II) Oxide was passed over a heated sample of an oxide of iron as shown in the diagram below. Study the diagram and the data and use it to answer the questions that follow
Mass of empty dish =6.72g
Mass of empty dish + oxide of iron =9.04g
Mass of empty dish + residue=8.40g
(a) Determine the formula of the oxide of iron given that the relative formula mass of oxide of Iron = 232, Fe = 56.0, O=16.0
(b) Write an equation for the reaction which took place in the dish
Date posted: March 26, 2019. Answers (1)
- The elements A and B have the following properties(Solved)
The elements A and B have the following properties
(a) When the isotope A was bombarded with a neutron, an isotope C was formed .Fill in the table to show the properties of element C
(b)Write an equation for the reaction between isotope B and Beta particles
(c) State one use of radioisotopes in medicine.
Date posted: March 26, 2019. Answers (1)
- The set up below was used to electrolyze molten lead (II) bromide.(Solved)
The set up below was used to electrolyze molten lead (II) bromide.
(a) State the observation that was made at the anode during electrolysis.
(b) A current of 2.5A was passed for 30 minutes. Calculate the mass of lead that was deposited
Date posted: March 26, 2019. Answers (1)
- Use the information below and answer the questions that follow .The letters are not the actual symbols of the elements.(Solved)
Use the information below and answer the questions that follow .The letters are not the actual symbols of the elements.
(a) Calculate the E? value for the electrochemical cell represented below.
(b) Arrange the elements in order of reactivity starting with the least reactive.
(c) Explain if it would be advisable to store element G in a solution containing E2+ Ions.
Date posted: March 26, 2019. Answers (1)
- The table below gives some properties of three elements X,Y and Z.(Solved)
The table below gives some properties of three elements X,Y and Z.
(a) Which element is in liquid form at room temperature? Give reason.
(b) Explain why the boiling point of element X is higher than that of element Z.
Date posted: March 26, 2019. Answers (1)
- The diagram below is a cross section of a dry cell. Study it and answer the questions that follow.(Solved)
The diagram below is a cross section of a dry cell. Study it and answer the questions that follow.
(i) Write the equation for the reaction in which electrons are produced.
(ii) The Zinc can is lined with Ammonium Chloride and Zinc Chloride paste. What would happen if the mixture was to become dry? Give reason.
Date posted: March 26, 2019. Answers (1)
- The electron arrangement of ions Q2- and R3+ are as 2, 8, 8, and 2,8respectively.
(a) Write the electron arrangement of the elements Q and R...(Solved)
The electron arrangement of ions Q2- and R3+ are as 2, 8, 8, and 2,8respectively.
(a) Write the electron arrangement of the elements Q and R
(b) Write the formula of the compound that would be formed between Q and R
Date posted: March 26, 2019. Answers (1)
- Study the flow chart below and answer the questions that follow.(Solved)
Study the flow chart below and answer the questions that follow.
i) Name the process in step I and the conditions for the reaction in step I
Name of process
Conditions
ii) Identify substance N
iii) Give
I. One disadvantage of the continued use of substance such as M
II. The name of the process that takes place in step III
III. The name and structural formula of the substance Q
Name
Structural formula
Date posted: March 26, 2019. Answers (1)
- Below is a set up of the apparatus that is used to prepare sulphur trioxide.
Name
I. – Gas N -
II. – Gas M –
III. – Catalyst...(Solved)
Below is a set up of the apparatus that is used to prepare sulphur trioxide.
Name
I. – Gas N -
II. – Gas M –
III. – Catalyst –
IV. – Solid Y –
Date posted: March 25, 2019. Answers (1)
- What factors should be considered when siting a plant to manufacture sulphuric acid?(Solved)
What factors should be considered when siting a plant to manufacture sulphuric acid?
Date posted: March 25, 2019. Answers (1)
- List down different types of amorphous sulphide.(Solved)
List down different types of amorphous sulphide.
Date posted: March 25, 2019. Answers (1)
- Why is it necessary to vulcanise natural rubber before use?(Solved)
Why is it necessary to vulcanise natural rubber before use?
Date posted: March 25, 2019. Answers (1)
- Name one substance used for vulcanisation of rubber.(Solved)
Name one substance used for vulcanisation of rubber.
Date posted: March 25, 2019. Answers (1)
- List four ammonium salts and state the uses of each.(Solved)
List four ammonium salts and state the uses of each.
Date posted: March 25, 2019. Answers (1)
- Explain how carbon monoxide is lethal when one inhales.(Solved)
Explain how carbon monoxide is lethal when one inhales.
Date posted: March 25, 2019. Answers (1)
- State six uses of carbon dioxide.(Solved)
State six uses of carbon dioxide.
Date posted: March 25, 2019. Answers (1)
- How many molecules, by avogadro’s number does 0.32g of oxygen gas has?(Solved)
How many molecules, by avogadro’s number does 0.32g of oxygen gas has?
Date posted: March 25, 2019. Answers (1)
- What mass of Lead (II) nitrate could contain 13g of Lead?(Solved)
What mass of Lead (II) nitrate could contain 13g of Lead?
Date posted: March 25, 2019. Answers (1)
- How many calcium ions and chloride ions are in 1 mole of calcium chloride, CaCl2?.(Solved)
How many calcium ions and chloride ions are in 1 mole of calcium chloride, CaCl2?.
Date posted: March 25, 2019. Answers (1)