Question

Among – 1A elements which can form ionic as well as covalent bonds?
A. Hydrogen
B. Cerium
C. Helium
D. Sodium

Answer 1

Elements are arranged in a tabular form called periodic table and there are 115 elements present in the periodic table. There are similarities as well as differences in the properties of these elements. On the basis of these properties, elements can be divided into metals and non-metals.

Complete answer:
Covalent bond is the bond formed between hydrogen and chlorine that is formed between these two species because of their varying electronegativities which tends them to become polarized. This happens because the more electronegative atom which is chlorine in this case pulls the bond pair of electrons closer to itself by developing a partially negative charge on it and positive charge on hydrogen.
An ionic compound is a chemical compound composed of ions that are held together by electrostatic forces which in general is known as ionic bonding and the main characteristic of ionic compounds is they are overall neutral. Ionic compound is generally composed of two types of ions out of which one is positively charged known by the name cation and other is negatively charged known as anions. When they dissociate they form anion and cation.
Out of the given elements hydrogen is the lightest element in the periodic table. Hydrogen generally forms covalent compounds with non-metals while in ionic compounds hydrogen can form the negative charge which is known as hydride or cation.

Thus, option A is the correct answer.

Note:
The strength of a covalent bond is highly dependent on the electronegativities of the two bonded atoms or we can say that the difference between the electronegativities of the bonded atoms.