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Study the information in the table below and answer the questions that follow, letters do not represent actual symbols of the element.

Study the information in the table below and answer the questions that follow, letters do not represent actual symbols of the element.
Q29202019816.png

a) Write the electronic configuration of an ion of elements T and U.
b) Why do the elements represented by R and S have two values of melting point.
c) Select an element:
i) Which is the most electronegative.
ii) That belongs to period 4, explain.
d) Explain why:
i) Ionic radius of R is bigger than its atomic radius.
ii) The atomic radius of L is bigger than that of R yet they are in the same period.
e) Using dots (.) and cross (x) to represent outermost electron show bonding in the compound formed between L and M.

f) Write an equation for the reaction that occurs between U and water.
g) Describe how a solid mixture of the sulphate of element N and lead (II) sulphate can be separated into solid sample of dry lead (II) sulphate.

Answers

Maurice
a)T- 2.8.7
U-2.8.8.1

b) because of the presence of allotropes

c) i) T
ii) U
Explanation:Because it has four energy levels.

d) i) R form ions by gaining electrons. The incoming electrons cause electron repulsion that makes the energy level to bulge out increasing the size
ii) The nuclear charge increases from L to R hence an increase in nuclear attraction which pulls the energy levels to the
nucleus.

e) L - 2.1
M – 2.7

f) U-19-2.8.8.1

2U(s) + 2H2O(l)----->2UOH(aq) + H2(g)


g) Add water to the mixture.
Filter the mixture to remove PbSO4 as residue.
Wash the residue with distilled water.
Dry between two filter papers.
maurice.mutuku answered the question on September 20, 2019 at 05:27

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