Question

(1) An element with the atomic number 19 will
most likely combine chemically with the
element whose atomic number is:
(a) 17
(b) 11
(c) 18
(d) 20​

Answer 1

Answer: 17

Explanation:

The electronic configuration of the element with atomic number 19 is 2,8,8,1

So it is highly reactive due to presence of an electron in its outer shell and will try to lose the electron. Element with atomic number 17 has the electronic configuration as 2,8,7-hence it will try to gain an electron to complete octet. The remaining elements given in the options do not satisfy the required conditions.

Hence the answer is 17

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Answer 2

Answer:19 is potassium and [a] is the answer which is chlorine

Explanation:

[b] is sodium which is a metals and  metals don't react which other metals under normal circumstances

[c] 18 is argon which is a noble gas and does not react with other substances as its shells are filled of electrons

[d] is calcium which is a metals and  metals don't react which other metals under normal circumstances

and {a} which is the right answer as it is a nonmetal which reacts with metals

above than it is a halogen which are the most reactive nonmetal

above than again it is chlorine which is only second in the non metal reactivity  series

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