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The grid below represents part of the periodic table. Study it and answer the questions that follow. The letters do not represent the actual symbols...

The grid below represents part of the periodic table. Study it and answer the questions that follow. The letters do not represent the actual symbols of the element.


a) What name is given to the group of elements to which Q and R belong?
b) Write the formula of the compound formed when Q and P combine.
c) Name the type of bond formed in (b) above.
d) How does the atomic radii of O and P compare? Give a reason.
e) Draw a dot (.) and cross (x) diagram for the compound formed between N and F.
f) Explain how you would obtain a pure sample of the carbonate of K from its mixture with Lead carbonate powder.
g) Give one use of element M.
h) The melting point of M is -189^oC lower than that of F -102^oC. Explain this difference in their melting points.

Answers

a) Alkaline earth metals

b) Q²P²----->QP – NB: metal should be followed by a non-metal and not vice versa.

d) The atomic radius of P is smaller than that of O. P has higher/stronger nuclear force of attraction than O P has more number of protons than O.

e)

f) Add water to the mixture of K carbonate and lead carbonate and stir. K carbonate dissolves while lead carbonate does not.
Filter to obtain K carbonate solution as a filtrate and lead carbonate as the residue.
Evaporate the filtrate to obtain crystals of carbonate of K Wash the residue with distilled water and dry between filter papers.

g) -Used in light bulbs to provide an inert environment to prevent oxidation.
-Used as an insulator in arch – welding.

h) M is a monoatomic gas while F is a diatomic gas; the Van der waal forces in M are weaker than in F hence the low m.p.t

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maurice.mutuku answered the question on September 11, 2019 at 05:53

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