Ethylene glycol is used as an antifreeze in a cold climate. Mass of ethylene glycol which should be added to 4 kg of water to prevent it from freezing at −6^oC will be : [K_f for water = 1.86 K kg mol⁻¹ , and molar mass of ethylene glycol = 62 g mol⁻¹ )

Outer electronic configuration of Gd (Atomic no : 64) is -

The outer electron configuration of $$Gd$$ (Atomic No. $$64$$) is :

Phenol is heated with a solution of mixture of KBr and KBrO₃. The major product obtained in the above reaction is