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Aluminium reacts with oxygen to form aluminium oxide which coats the surface of the article.
sharon kalunda answered the question on May 16, 2019 at 12:35
- A mixture of carbon (IV) Oxide and carbon (II) oxide is passed through potassium hydroxide
solution as shown in the following set up.(Solved)
A mixture of carbon (IV) Oxide and carbon (II) oxide is passed through potassium hydroxide
solution as shown in the following set up.
I) Name gas X
(ii) Why should gas X be burned.
(iii) Write a well balanced chemical equation for the reaction that takes place in the conical
flask in the first few seconds.
Date posted: May 16, 2019. Answers (1)
- Write ionic equations for electrolysis of dilute sulphuric acid using platinum electrodes at:(Solved)
Write ionic equations for electrolysis of dilute sulphuric acid using platinum electrodes at:
(i) Anode
(ii) Cathode
Date posted: May 16, 2019. Answers (1)
- Dilute hydrochloric acid is warmed with sodium sulphide.State a chemical test for the gas evolved.(Solved)
Dilute hydrochloric acid is warmed with sodium sulphide.State a chemical test for the gas evolved.
Date posted: May 16, 2019. Answers (1)
- 100cm3 of 2M Nitric acid reacted with 12.5g of a carbonate MCO3 of metal M, calculate the relative atomic mass of M ( C =...(Solved)
100cm3 of 2M Nitric acid reacted with 12.5g of a carbonate MCO3 of metal M, calculate the relative atomic mass of M ( C = 12, O = 16)
Date posted: May 16, 2019. Answers (1)
- A white solid K was heated. It produced a brown gas A and another gas B which relights a
glowing splint. The residue left was yellow...(Solved)
A white solid K was heated. It produced a brown gas A and another gas B which relights a
glowing splint. The residue left was yellow even after cooling.
a) Identify gases A and B
b) Write a balanced chemical equation for the decomposition of solid K.
Date posted: May 16, 2019. Answers (1)
- Below is a set up used to collect hydrogen gas.(Solved)
Below is a set up used to collect hydrogen gas.
a) Identify with reasons, two mistakes in the set up.
b) Explain the role of hydrogen in the manufacture of margarine.
Date posted: May 16, 2019. Answers (1)
- Complete the following reactions.(Solved)
Complete the following reactions.
Date posted: May 16, 2019. Answers (1)
- The scheme below shows some reaction sequence starting with solid M(Solved)
The scheme below shows some reaction sequence starting with solid M
(i) Name Solid M
(ii) Write the formula of complex ion present in Solution Q
(iii) Write ionic equation of reaction between barium nitrate and solution N.
Date posted: May 16, 2019. Answers (1)
- What is the oxidation number of chlorine in ClO-4?(Solved)
What is the oxidation number of chlorine in ClO-4?
Date posted: May 16, 2019. Answers (1)
- Identify the acid and base in the equation below.(Solved)
Identify the acid and base in the equation below.
Date posted: May 16, 2019. Answers (1)
- In terms of structure and bonding explain why diamond has a high melting point while
graphite has a low melting point.(Solved)
In terms of structure and bonding explain why diamond has a high melting point while
graphite has a low melting point.
Date posted: May 16, 2019. Answers (1)
- A compound G reacts with 2 moles of bromine to form another compound whose graphical
formula is.(Solved)
A compound G reacts with 2 moles of bromine to form another compound whose graphical
formula is.
i) What is the formula and name of compound G
ii) State the observations made when acidified potassium chromate (VI) is
added to compoundG
Date posted: May 16, 2019. Answers (1)
- Explain why the compound Cl2O has a very low melting and boiling point.(Solved)
Explain why the compound Cl2O has a very low melting and boiling point.
Date posted: May 16, 2019. Answers (1)
- Two elements A and B have electronic configurations 2.8.3 and 2.6 respectively.(Solved)
Two elements A and B have electronic configurations 2.8.3 and 2.6 respectively.
a) To which group and period does element B belong?
b) If the two react, what is the formula of the compound they form
Date posted: May 16, 2019. Answers (1)
- The graph below shows the decay for a sample of 400g of iodine -131. Study is and
answer question that follow.(Solved)
The graph below shows the decay for a sample of 400g of iodine -131. Study is and
answer question that follow.
(i) Use the graph to determine the half-life of the sample
(ii) What fraction of the original sample remains after 16.2 days.
Date posted: May 16, 2019. Answers (1)
- Define the following terms(Solved)
Define the following terms
(i) Nuclear fission
(ii) Nuclear fussion.
Date posted: May 16, 2019. Answers (1)
- The scheme below represents some reaction involving hydrocarbons. Study it and
answer the questions that follow.(Solved)
The scheme below represents some reaction involving hydrocarbons. Study it and
answer the questions that follow.
(i) Name Compound P.
(ii) Draw the structural formula of P.
(iii) Name the reagent and type of reaction taking place in process R.
(iv) What is a polymer.
(v) Identify the reagent used in Step 1
Date posted: May 16, 2019. Answers (1)
- Write an equation of reaction between ethene and chlorine gas and name the
product.(Solved)
Write an equation of reaction between ethene and chlorine gas and name the
product.
Date posted: May 16, 2019. Answers (1)
- Name the following compounds.(Solved)
Name the following compounds.
Date posted: May 16, 2019. Answers (1)
- Lead (II) ions react with iodide ions according to the equation(Solved)
(i) Lead (II) ions react with iodide ions according to the equation
300cm3 of 0.1M solution of iodide ions was added to a solution containing Lead (II)
ions. Calculate the mass of Lead (II) iodide formed (Pb= 207, I = 127).
(ii) Identify the colour of the product formed after the reaction above.
Date posted: May 16, 2019. Answers (1)