Answer:
These are the properties of a substance which can be observed without changing the physical appearance of a substance.
Example :
(i) Boiling Point: Water has a boiling point of 100 °C at sea level. At this temperature the water changes its state from liquid to vapors (gas).
(ii) Melting Point: Water has a melting point of 0 °C. At this temperature the water changes its state from solid to liquid.
(iii) Freezing Point: Water has a melting point of 0 °C. At this temperature the water changes its state from liquid to solid.
(iv) Density: The density of water is about 1 g/ml at 20 °C.
(iii) Heat Capacity: Heat capacity of water is 4.186 joule/gram °C.
These are the properties of a substance which can be observed only by changing the identity of a substance.
Example :
(i) Stable Compound: Water is said to be a very stable compound. It means it cannot decompose easily. Hence, has a stable bonds. This stability can be termed as chemical property.
(ii) Reactions with Metals: With reaction with metals the water produces hydrogen gas and corresponding metal hydroxide.
(iii) Reactions with Metal Oxides: Upon reaction with metal oxides water produces bases.
(iv) Reactions with Non-Metals: Upon reaction with non-metals water produces corresponding acids.
