(I) boiling is a physical property you can boil water and it will not change into another substance.
(II) color is a physical property. It is describing the object. Your shoes are blue, am I adding anything to make it orange? No. It is blue and nothing is changing the color.
(III) objects made of silver is a chemical prop. Like how your bike rusts..your bike rusts because iron is CHANGING into iron oxide. It reacts with the oxygen in the air and rusts.
Physical properties are all descriptions. Water is clear, the boiling point of water is... chemical prop is your bike rusts etc.