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Helium is light and inert thus will not burn in air like Hydrogen.
sharon kalunda answered the question on May 16, 2019 at 12:46
- A solution containing 0.1m sulphuric acid has a pH of 2 while 5M has a pH of more than two.
Explain.(Solved)
A solution containing 0.1m sulphuric acid has a pH of 2 while 5M has a pH of more than two.
Explain.
Date posted: May 16, 2019. Answers (1)
- When a current of 2.5 amperes was passed through a cell containing N2+ ions of a metal for 25 minutes, the mass of the cathode increased by...(Solved)
When a current of 2.5 amperes was passed through a cell containing N2+ ions of a metal for
25 minutes, the mass of the cathode increased by 0.36g. ( 1 faraday = 96500 coulombs).Determine the relative atomic mass of element N.
Date posted: May 16, 2019. Answers (1)
- State and explain the observation made in the set-up below.(Solved)
State and explain the observation made in the set-up below.
Date posted: May 16, 2019. Answers (1)
- Explain why aluminium articles are not easily corroded.(Solved)
Explain why aluminium articles are not easily corroded.
Date posted: May 16, 2019. Answers (1)
- 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)