Question 5
How do you define a chemical change?
Give two or three examples of chemical change.
Choose the correct characteristic(s) about the chemical change from the following
Characteristic 1: chemical changes are irreversible
Characteristic 2: new substances are formed.
Characteristic 3: properties of new substances are the same as the properties of original substances.
The change in which the composition of the substance changes leading to the formation of new substances is called a chemical change.
Examples of chemical changes: burning of candle wax and burning of wood, etc.
Characteristics 1 and 2 are correct. During a chemical change, the properties of new substances are different from the properties of the original substances. Therefore, characteristic 3 is wrong.