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(a) Atomic No. of A 23 – 12 = 11
A = 2. 8 . 1
B = 2 . 1
(b) B,Its outermost electron experience stronger nuclear attraction / B has smaller
atomic radius/ has fewer energy levels.
sharon kalunda answered the question on May 21, 2019 at 06:57
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Date posted: May 21, 2019. Answers (1)
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Date posted: May 21, 2019. Answers (1)
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Zinc powder
Nitric (V) acid...(Solved)
Using reagents provided only, explain by means of balanced chemical equations how you
could prepare a salt of Zinc carbonate solid.
Zinc powder
Nitric (V) acid (dilute)
Water
Solid sodium carbonate
Date posted: May 21, 2019. Answers (1)
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Determine the number of protons and neutrons in the nuclide.(Solved)
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Date posted: May 21, 2019. Answers (1)
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(i) Volume of chlorine at (r.t.p) required to react with 3g of Aluminium (Molar gas volume at r.t.p =...(Solved)
Given the equation for reaction below
Calculate
(i) Volume of chlorine at (r.t.p) required to react with 3g of Aluminium (Molar gas volume at r.t.p = 24litres, Al = 27, Cl = 35.5).
(ii) Mass of Aluminium chloride formed.
Date posted: May 21, 2019. Answers (1)
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Mass of evaporating dish = 23.0g
Mass of evaporating dish + sample of saturated...(Solved)
Calculate the solubility of sugar in water at 40oC from the following information.
Mass of evaporating dish = 23.0g
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Mass of evaporation dish + solid after evaporating of solution + 142.0g
Date posted: May 21, 2019. Answers (1)
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Date posted: May 21, 2019. Answers (1)
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(i) Write an...(Solved)
The apparatus below was a set up to show the catalytic oxidation of ammonia. Study the diagram and answer the questions that follow.
(i) Write an equation for the reaction that takes place in the gas jar.
(ii) Why is it necessary to have a hot nichrome wire in the gas jar.
Date posted: May 21, 2019. Answers (1)
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Identify:
Gas P
Solid R
Solid T .
Liquid S(Solved)
Use the chart below to answer the questions that follow.
Identify:
Gas P
Solid R
Solid T .
Liquid S
Date posted: May 21, 2019. Answers (1)
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Date posted: May 21, 2019. Answers (1)
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(i) To what terminal of the power source is the key connected
(ii) Name the most suitable material for electrode K
(iii) Write the
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Date posted: May 21, 2019. Answers (1)
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(i) Solution
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(i) Solution
(ii) A metal
Date posted: May 21, 2019. Answers (1)
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(a) (i) Name the type of reaction...(Solved)
The scheme below shows a series of reactions starting with Propanol. Study it and answer the questions that follow.
(a) (i) Name the type of reaction in steps I and II
(b) Write the equation for the reaction that takes place in Step III
(c) Name substances labeled A,C,D and E
(d) Draw the structural formula of product C .
(e) Name the process in Step (IV).
(f) Name compound B and state the type of reaction involved in its formation
Name of compound B……………………………………………………………
Type of reaction………………………………………………………………….
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Date posted: May 21, 2019. Answers (1)
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(i) Name liquids A and B
(ii) Suggest a suitable reagent that can be...(Solved)
Study the diagram below and use it to answer the questions that follow.
(i) Name liquids A and B
(ii) Suggest a suitable reagent that can be used as solid D
(iii) State the role of Solid D
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Date posted: May 20, 2019. Answers (1)
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(i) Explain why the melting point and boiling points of MgCl2 are...(Solved)
Study the information given in the table below and answer the questions that follow.
(i) Explain why the melting point and boiling points of MgCl2 are very high yet melting
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Date posted: May 20, 2019. Answers (1)
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The table below shows some properties and electronic arrangement of ions of elements represented by letters P to X. Study the information and answer the questions that follow. The letters are not the actual symbols of elements.
(i) Give the atomic numbers of elements T and V
(ii) What is the name given to the family of elements to which R,V and W belong.
(iii) Explain why:
I .The atomic radius of S is smaller than that of V
II. the atomic radius of R is larger than its ionic radius
(iv) Using dots (•) and crosses (x) to represent outermost electrons, show the bonding in
the compound formed between U and X
(v) Describe how a mixture of V chlorine s Lead(II) chloride can be separated
Date posted: May 20, 2019. Answers (1)
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(i) Write a chemical equation for the reaction that occurs.
(ii) Determine...(Solved)
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(i) Write a chemical equation for the reaction that occurs.
(ii) Determine the composition of the residual gases.
Date posted: May 20, 2019. Answers (1)
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