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a) Valency of G is 3
b) G is a group 3 element
maurice.mutuku answered the question on October 14, 2019 at 09:47
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An element M has two isotopes M and M . The relative atomic mass of the naturally occurring is 63.55. Calculate the percentage of each isotope
Date posted: October 14, 2019. Answers (1)
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Given that isotope C contains 31 neutrons in its nucleus,find the number of protons in isotope B
Date posted: October 14, 2019. Answers (1)
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Date posted: October 14, 2019. Answers (1)
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Date posted: October 14, 2019. Answers (1)
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In an experiment an unknown mass of anhydrous sodium carbonate was dissolved in water and the solution made up to 250cm3. 25cm3 of this solution neutralized 20cm3 of 0.25M nitric acid.
(Na = 23.0 C = 12.0 O = 16.0)
Calculate:
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(c) Mass of unknown sodium carbonate used
Date posted: October 14, 2019. Answers (1)
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Date posted: October 14, 2019. Answers (1)
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(b) Why was it necessary to heat wet sand before heating Zinc granules?
Date posted: October 14, 2019. Answers (1)
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When hydrogen is burnt and the product cooled, the following results are obtained as shown in the diagram below:
(a) Write the equation for the formation of liquid Y
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Date posted: October 14, 2019. Answers (1)
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Gas P was passed over heated magnesium ribbon and hydrogen gas was collected as shown in the diagram below:
(i) Name gas P
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Date posted: October 14, 2019. Answers (1)
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(a) Identify solid X and state its purpose
Solid X
Purpose
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Date posted: October 14, 2019. Answers (1)
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In an experiment, dry hydrogen gas was passed over hot copper (II) oxide in a combustion tube as shown in the diagram below:-
Complete the diagram to show how the other product, substance R could be collected in the laboratory.
Date posted: October 14, 2019. Answers (1)
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(i) What causes this ignition?
(ii) Write an equation to show...(Solved)
When water reacts with potassium metal the hydrogen produced ignites explosively on the surface of water.
(i) What causes this ignition?
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Date posted: October 14, 2019. Answers (1)
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Date posted: October 14, 2019. Answers (1)
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(a) Write chemical equation for the reaction which can be used to...(Solved)
Fe3O4 and FeO are oxides of iron which can be produced in the laboratory
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Date posted: October 14, 2019. Answers (1)
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A piece of phosphorous was burnt in excess air. The product obtained was shaken with a small amount of hot water to make a solution
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Date posted: October 14, 2019. Answers (1)
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The electron configuration of elements A, B, C, D and E are as given below.
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c} Which letter represents the most reactive non-metal.
Date posted: October 14, 2019. Answers (1)
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Date posted: October 14, 2019. Answers (1)
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Element W has two isotopes W – 36 and W-40 which occur in the ratio x:4. Given that R.A.M of W is 37.25, find the value of x.
Date posted: October 14, 2019. Answers (1)
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Gas X and Y can be collected as shown below.
[a] Name the method used to collect gas Y.
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Date posted: October 14, 2019. Answers (1)
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{a} Name one other raw material(Solved)
In the industrial manufacture of Ammonia one of the raw materials is nitrogen gas
{a} Name one other raw material
{b} Name two possible sources of the raw material you have named in {a} above
{c} Name two substances that can be used as catalyst in this process
{d} State one use of ammonia
Date posted: October 14, 2019. Answers (1)