Answer:
True
Explanation:
The physical changes are reversible in most cases and these changes are not the chemical changes which means that it is only the change in its state not in their nature. Just take the example of water, on cooling it becomes solid and change in color can be seen which is white in solid form and colorless in liquid form. This is also reversible and is a physical change. This means that physical changes can be identified at macroscopic level. Hence the answer is true.
Answer: 1.
: oxidation reduction
2.
: precipitation
3.
: Double displacement
Explanation:
Oxidation-reduction reaction or redox reaction is defined as the reaction in which oxidation and reduction reactions occur simultaneously.
Oxidation reaction is defined as the reaction in which a substance looses its electrons. The oxidation state of the substance increases.Reduction reaction is defined as the reaction in which a substance gains electrons. The oxidation state of the substance gets reduced.

Double displacement reaction is defined as the reaction where exchange of ions takes place. Double displacement reaction in which one of the product remain in solid form are represented by (s) after their chemical formulas. Such double displacement reaction are called as precipitation reaction.

Double displacement reaction is defined as the reaction where exchange of ions takes place.

Single displacement reaction is defined as the reaction where more reactive element displaces a less reactive element from its chemical reaction.
Decomposition reaction is defined as the reaction where a single substance breaks down into two or more simpler substances.
Synthesis/Combination reaction is defined as the reaction where substances combine in their elemental state to form a single compound.
Answer:
Energy is released.
Explanation:
When an electron absorbs energy, it moves up into an excited state. When it releases energy, it will return to the ground state.
It is called Condensation