Question

In the table below, H does not represent hydrogen. Some elements are given in their own symbol and position in the periodic table while others are shown with a letter.

IA	IIA	IIIA	IVA	VA	VIA	VIIA	O
1	2	13	14	15	16	17	18
Li		D			O	J	Ne
A	Mg	E	Si		H	K
A	C		F	G			L

Select from the table.

1. Which is most electronegative.
2. How many valence electrons are present in G.
3. Write the formula of the compound between B and H.
4. In the compound between F and J what type of bond will be formed.
5. Draw the electron dot structure for the compound formed between C and K.

Answer 1

(i) J  is the most electronegative.

(ii) G has group 15 or VA, indicating it will have 5 electrons in its outermost shell.

(iii) B has one valence electron and its valency is +1. It is represented as B¹⁺.

H has 6 valence electrons, resulting in a valency of −2 (represented as H²⁻).

Chemical formula= 

(iv) F belongs to the 14th group, also known as IVA group. Four valence electrons indicate a covalent bond where electrons are covalent.

(v) C and K have two and seven valence electrons, respectively. To complete an octet, K requires one electron, while C requires two electrons to lose.