The grid below shows part of the periodic table. Study it and answer the questions that follows. a) Give the name of the elements represented by...

The grid below shows part of the periodic table. Study it and answer the questions that follows.

a) Give the name of the elements represented by the shaded region.
b) Identify an element which form ion with +2 charge.
c) Which non-metal is most reactive ?
d) Element V is in the second period and group V of the periodic table. Place it on the above grid of the periodic table.
e) State and explain how the atomic radius of U and J compare.
f) Write a chemical equation for the reaction between the oxide of A and water.
g) Explain how the electrical conductivity of A and Y compare.

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a) Transition elements / metals
b) J / Mg
c) K / Cl2
d) On the grid
e) The atomic radius of U is smaller than that of J
Reason : There is decrease in atomic radius across the period due to increase in the nuclear charge (no. of protons) thus pulling the outer electrons of U closer to the nucleus
f) A₂O(s) + H₂O(l) --> 2AOH(aq)
g) Y is a better conductor than A since it has more delocalised electrons than A

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Kavungya answered the question on May 24, 2019 at 13:00

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