the answer is: Atomic number
Answer: Option (B) is the correct answer.
Explanation:
A change which brings change in composition of atoms of a substance to result in the formation of new substances is known as a chemical change.
Therefore, in a chemical change new substances are formed which have different properties as compared to their reactants.
For example, 
Thus, we can conclude that during all chemical changes atoms rearrange to form new substances.
Answer:
The correct answer is GAMMA RADIATION.
Explanation:
Electromagnetic waves are waves that are created as the result of the interaction between the magnetic and the electric field. Gamma ray is a type of electromagnetic wave, it has the shortest wavelength compare to other electromagnetic waves, thus, it has high penetrating power. Gamma ray is an ionizing radiation, which can be a source of biological hazard.
Answer:
The rearrangement of particles in a physical change.
Explanation:
When things are liquid the particles tend to be spread out because they aren't tightly compacted as they would be with a solid. So when liquid gold is changing from a liquid to a solid the properties are changing and the particles in the gold are getting closer together.