The table below shows the atomic numbers of some elements represented by letter J to Q ( letters not their actual symbols). Study and answer the...

The table below shows the atomic numbers of some elements represented by letter J to Q ( letters
not their actual symbols). Study and answer the questions that follow.

a) Write the electronic configuration of
(i) M
(ii) P²⁺
b) Write the formula of the compound formed when L combines with N
c) How would reactivities of element N and P with chlorine compare? Explain.
d) Element N combines with oxygen to from an oxide. Using dots (.) and crosses(x) to
represent the outermost electrons, show how the two elements combine.
e) Select the most reactive metal and non-metal and give reason for your answer.
f) State one physical and one chemical property that elements J and Q have in common
g) What name is given to the group of elements to which element M belong?
h) (i) Element K consists of two isotopes with relative abundances 75% and 25% and
mass number 35 and 37 respectively find the relative atomic mass of K.
(ii) Why is the relative atomic mass of K not a whole number?

Answers

(a) (i) 2.8.4
(ii)2. 8. 8
(b) N₂M₃
(c) P reacts faster with chlorine than N
Because P is larger in size or its electrons are more
shielded from the positive nucleus
(d) N 2. 8. 2, O 2. 6

(e) Metal Q
Reason: has largest atomic radius therefore loses
electrons most readily metal M A transition
metal
(f) Physical: their freshly cut surface are shiny
Chemical – displace it from cold water / tarnish by air
(h) (i) (75 x 35 + 25 x 37)/100 = 35.5
(ii) Because existence of isotopes which differ in their
relative abundance
(g) Transition metal

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sharon kalunda answered the question on May 13, 2019 at 14:17

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