A substance which reacts with oxygen giving heat is called a combustible substance. Which, one of the following is a combustible substance?

(D) Blue Birds fly in air and air is called blue.

(B) A person stands on a floor and floor is called terrace.

correct answer is (C) Nose.

The correct answer is (D) Ink.

Earth is a planet and here planets are called aeroplanes. So, earth will be called aeroplanes.

Position of P Group-2 Because it has 2 valence electrons/ 2, S, 8, 2 Period-4 Because it has 4 shells/2,8,8,2 Position of Q Croup-17 Because it has 7 valence electrons/ 2, 8, 7 Period-3 Because it has 3 shells/...

The Right option is : (b) glass

(a) Combustible — charcoal, straw, card board, paper, candle wood,  (b) Non-combustible — chalk, stone, iron rod, copper coin, glass.

(ii) Electrophilic substitution reaction

(iii); The tertiary carbocation formed in the reaction is stable.