Classify each of the following changes as physical or chemical:
(a) coal burning
(b) ice melting
(c) mixing chocolate syrup with milk
(d) explosion of a firecraker
(e) magnetizing of a screwdriver

Explanation:

Physical changes are the changes that does not lead to any change in chemical composition of a substance.

For example, mass, density, volume are all physical changes.

On the other hand, a change that leads to formation of a new compound by changing the chemical composition of reactants or combining atoms is known as a chemical change.

For example, combustion, toxicity, reactivity etc are all chemical changes.

Therefore, given changes are identified as follows.

space exploration has led to the development and technological improvement of many everyday items. (if this answer is wrong i will find the right answer) : )