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The table below gives some elements of the periodic table and their atomic masses, atomic numbers and melting points. The letters are not the actual...

The table below gives some elements of the periodic table and their atomic masses, atomic numbers and melting points. The letters are not the actual symbols of the elements.

(a) Select two elements with oxidation states of -3.
(b) Which elements represent the most powerful reducing agent? Explain.
(c) Which element has the highest ionization energy?
(d) Select two elements which when reacted form a compound that conducts electricity both in molten and aqueous state.
(e) Select any two elements which when reacted form a compound that dissolves in water to form an acidic solution.
(f) Using dots (●) and crosses (X) to represent electrons; draw diagrams to show bonding between B and J.
(g) Explain why for some elements the atomic mass is not twice the atomic number.
(h) Explain why the melting point of element K is higher than that of element D.
(i) Describe how a solid mixture of the Sulphate of element K and lead (II) Sulphate can be separated.

Answers

a) B and E
b) D
c) F has smallest atomic radius hence electrons are strongly attracted by
positive nucleus
d) D and G //J and G//D and C//K and G (Any one above award for both)
e) B and C //I and C//E and C (Any one above award for both)
f)
g) Number of neutrons is not equal to the number of protons.
h) K has stronger metallic bonds since it has smaller atomic size hence
more energy is needed to break them.
i) - Add water to the mixture and stir
- Sulphate of K dissolves while lead (II) sulphate does not
- Filter , lead (II) sulphate as the residue while sulphate of K is the filtrate
- Evaporate the filtrate to dryness to obtain solid sulphate of K

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sharon kalunda answered the question on August 5, 2019 at 11:17

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