Complete the following by choosing the correct answer from the bracket.

(a) The number of electrons present in valence shell of a halogen is …………… (5/7).

(b) The degree of ionisation of an acid in an aqueous solution is called its ……………(strength/concentration)

(c) Pure nitric acid decomposes to give yellow solution on exposure to heat due to the formation of …………… (nitrogen dioxide/nitrogen trioxide)

(d) Hydrocarbon having triple bond is called …………… (alkene/alkynes)

(e) The commonly used catalyst for the conversion of ethene to ethane is …………… (nickel/iron).

(a) The number of electrons present in valence shell of a halogen is 7.

(b) The degree of ionisation of an acid in an aqueous solution is called its strength.

(c) Pure nitric acid decomposes to give yellow solution on exposure to heat due to the formation of nitrogen dioxide.

(d) Hydrocarbon having triple bond is called alkynes.

(e) The commonly used catalyst for the conversion of ethene to ethane is nickel.