Get premium membership and access questions with answers, video lessons as well as revision papers.
- During a displacement reaction, excess iron powder was added to 25cm3 of 0.5 M copper (II) sulphate solutions. The temperature rose from 18.5oC to 33.0oC....(Solved)
During a displacement reaction, excess iron powder was added to 25cm3 of 0.5 M copper (II) sulphate solutions. The temperature rose from 18.5oC to 33.0oC. Calculate the molar enthalpy of displacement of copper in copper (II) sulphate solution (Specific heat capacity is 4.2 Jg-1K-1, Density of the solution = 1.0g/cm3)
Date posted: May 13, 2019. Answers (1)
- Describe how you would prepare crystals of sodium nitrate starting with 200cm3 of 2M
sodium hydroxide.(Solved)
Describe how you would prepare crystals of sodium nitrate starting with 200cm3 of 2M
sodium hydroxide.
Date posted: May 13, 2019. Answers (1)
- The diagram below shows a set –up for preparation of hydrogen chloride gas.(Solved)
The diagram below shows a set –up for preparation of hydrogen chloride gas.
Write the equation for the reaction that produces hydrogen chloride gas.
Date posted: May 13, 2019. Answers (1)
- The following table gives the melting points of oxides of elements in period 3. Study it and
answer the questions that follow:-(Solved)
The following table gives the melting points of oxides of elements in period 3. Study it and
answer the questions that follow:-
(i) Explain the difference in melting points of MgO and P4O10
(ii) Name the compound in the above table that will dissolve both in dilute
hydrochloride acid and dilute sodium hydroxide.
Date posted: May 13, 2019. Answers (1)
- 36cm3 of a solution of potassium hydroxide requires 25cm3 of 0.5M sulphuric acid to
neutralize it.Calculate the concentration of alkali in g/dm3(Solved)
36cm3 of a solution of potassium hydroxide requires 25cm3 of 0.5M sulphuric acid to
neutralize it.Calculate the concentration of alkali in g/dm3
Date posted: May 13, 2019. Answers (1)
- Draw the structural formula of organic compound with the formula C5H10O2 giving its name. (Solved)
Draw the structural formula of organic compound with the formula C5H10O2 giving its name.
Date posted: May 13, 2019. Answers (1)
- The diagram below represents set-up that can be used to prepare and collect oxygen gas(Solved)
The diagram below represents set-up that can be used to prepare and collect oxygen gas
a) Name solid P
b) What property of oxygen makes it possible for its collection as indicated by the
diagram.
c) Explain why it is important not to collect any gas for the first few seconds of the
experiment.
Date posted: May 13, 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.
a) Identify N and P
b) What name is given to the type of halogenation/Chlorination reaction in step 2
Date posted: May 13, 2019. Answers (1)
- During the electrolysis of dilute sulphuric (VI) acid the volume of hydrogen gas collected is twice
the volume of oxygen gas. Using half equations justify the...(Solved)
During the electrolysis of dilute sulphuric (VI) acid the volume of hydrogen gas collected is twice
the volume of oxygen gas. Using half equations justify the above statement.
Date posted: May 13, 2019. Answers (1)
- Under certain conditions ,methane reacts with steam to form carbon (II) oxide and hydrogen only. Calculate the total volume of the gas that can be...(Solved)
Under certain conditions ,methane reacts with steam to form carbon (II) oxide and hydrogen only. Calculate the total volume of the gas that can be formed when 100cm3 of steam reacts completely with methane.
Calculate the enthalpy change of the reaction.
Date posted: May 13, 2019. Answers (1)
- Classify the following processes as either chemical or physical.(Solved)
Classify the following processes as either chemical or physical.
Date posted: May 13, 2019. Answers (1)
- The equation for dissolution of bismuth(III) chloride in water is(Solved)
The equation for dissolution of bismuth(III) chloride in water is
Explain the effect on the position of equilibrium if sodium hydroxide solution is added to the mixture at equilibrium.
Date posted: May 13, 2019. Answers (1)
- State the Lechateiler’s principle.(Solved)
State the Lechateiler’s principle.
Date posted: May 13, 2019. Answers (1)
- Carbon(IV) oxide is one of the main contributor to global warming.
Name two other gases.(Solved)
Carbon(IV) oxide is one of the main contributor to global warming.
Name two other gases.
Date posted: May 13, 2019. Answers (1)
- Using a suitable equation explain why it is not advisable to use hardwater in hot water
systems.(Solved)
Using a suitable equation explain why it is not advisable to use hardwater in hot water
systems.
Date posted: May 13, 2019. Answers (1)
- The catalytic oxidation of ammonia gas is done as per the set up below.(Solved)
The catalytic oxidation of ammonia gas is done as per the set up below.
a) Name the catalyst used in the above reaction.
b) After sometime, brown fumes are formed in the flask. Explain briefly how this
observation occurs.
c) Why does the metal catalyst stay red hot for some time?
Date posted: May 13, 2019. Answers (1)
- Below is a table of 1st ionization energies for elements A,B,C, and D which are metals.(Solved)
Below is a table of 1st ionization energies for elements A,B,C, and D which are metals.
a) What is meant by 1st ionization energy?
b) With an explanation, arrange the elements in order of increasing reactivities.
Date posted: May 13, 2019. Answers (1)
- Hydrogen gas is one of the lightest gas known but has not lived to its expectation to be used inObservation balloons. Explain(Solved)
Hydrogen gas is one of the lightest gas known but has not lived to its expectation to be used inObservation balloons. Explain
Date posted: May 13, 2019. Answers (1)
- Describe how you would prepare a sample of iron(II)carbonate,starting with iron metal and dilute hydrochloric acid.(Solved)
Describe how you would prepare a sample of iron(II)carbonate,starting with iron metal and dilute hydrochloric acid.
Date posted: May 13, 2019. Answers (1)
- When 1.15g of R were reacted with water, 600cm3 of gas was produced.
Determine the relative atomic mass of R. (Molar gas volume = 24 000...(Solved)
When 1.15g of R were reacted with water, 600cm3 of gas was produced.
Determine the relative atomic mass of R. (Molar gas volume = 24 000 cm3).
Date posted: May 7, 2019. Answers (1)