How do you know if a chemical reaction is present

When two or more reactants are mixed and a change in temperature, color, etc. is noticed, a chemical reaction is probably occurring. However, these are not definite indicators.

Explanation: In a chemical reaction, there is a change in the composition of the substances. The following are indicators of chemical changes:

Change in Temperature

Change in Color

Noticeable Odor (after reaction has begun)

Formation of a Precipitate

Formation of Bubbles

the potential energy of the reactants is 200j.

from the energy diagram, the energy of the product formed is 350j; this means that, this reaction is an endothermic reaction, because it absorbs energy from its environment.

periodic trends is an atom that gets larger as the number of electronic shells increase, the radius of atoms increases as you go down a certain group in the periodic table of elements. in general, the size of an atom will decrease as you move from left to right of a certain period.