24. The elements in group 7 of the periodic table are known as the halogens. square point in "C point in "C atomie mass elen melting boiling relative te (d) An iron nail is placed into some blue copper sulphate solution. A reaction takes place between the iron and the copper sulphate. (i) Complete the word equation for the reaction. iron + copper sulphate > __ __ (ii) Describe one change you would see on the surface of the nail. __ n