1. II.
Magnesium hydroxide and nitric acid (HN2O) react to produce magnesium nitrate
and water. (2)
Aluminium bromide and chlorine react to produce aluminium chloride and
bromine. (2)
Sodium phosphate and calcium chloride reacts to produce calcium phosphate
and sodium chloride. (2)

Why is the temperature constant during the melting of water?

THE HEAT WE R SUPPLYING TO THE WATER TO RAISE THE TEMP OF THE WATER IS USED BY THE MOLECULES TO BREAK INTERMOLECULAR BONDS WHICH HELP IN THE CHANGING OF THE LATTICE (STRUCTURE) OF THE WATER .

ICE HAS A HEXAGONAL RING LIKE STRUCTURE WHICH IS CONVERTED INTO REGULAR CRYSTALLINE STRUCTURE WHICH CAN ONLY BE FORMED WITH THE HELP OF FORMATION OF NEW BONDS AND BREAKDOWN OF OLDER ONES

THE AMOUNT OF ENERGY WHICH IS USED IN CONVERSATION OF THE STATE OF FROM SOLID TO LIQUID IS KNOWN AS LATENT HEAT OF FUSION.

SO TEMP REMAIN CONSTANT DURING CHANGE IN STATE .