Question

Which of these necessarily changes during a chemical change?​

Answer 1

Answer:

 When chemical reactions occur, the atoms are rearranged and the reaction is accompanied by an energy change as new products are generated. An example of a chemical change is the reaction between sodium and water to produce sodium hydroxide and hydrogen.

Explanation:

Answer 2

a) Smell

b) Taste

c) Colour

d) Evolution of gas