Question

Atoms of seven elements A, B, C, D, E, F and G have

a different number of electronic shells but have the

same number of electrons in their outermost shells.

The elements A and C combine with chlorine to form

an acdi and common salt respectively. The oxide of

element A is a liquid at room temperature and is a

neutral substance, while the oxides of the remaining

six elements are basic in nature. Based on the above

information answer the following questions.

i. What could the element A be ?

ii. Will elements A to G belong to the same period

or same group of the periodic table ?

iii. Write the formula of the compound formed by

the reaction of element A with oxygen.

iv. Show the formation of the compound by a

combination of element C with chlorine with the

help of an electronic structure.

v. Which one of the given elements is likely to have

the smallest atomic radius ? ​

Answer 1

Answer :

i. Hydrogen.

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ii.Elements A to G will belong to the same group of the periodic table since they contain the same number of electrons in their outermost shells or in other words, the valence electrons of both the elements are same.

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iii. Since the element A is hydrogen, reaction will be:-

• $\rm{2H_2+O_2\longrightarrow{}2H_2O}$

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iv. Compound formed is CCl. Please refer to the attached image to see the formation of the same.

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v. Element A (which is hydrogen) is likely to have the smallest atomic radius amongst all the elements in the group. This is because the atomic radius increases while moving down the group.

Answer 2

Answer:

I) hydrogen

ii) same group

iii) H2O

iv) I have attached a picture for this answer.

v) 1:4

vi) A