Answer:
- <u><em>Option A) A gas was produced.</em></u>
Explanation:
Indeed, the production of a gas is an indication that a new substance was produced as result of the reaction of the matter that constitutes the antiacid tablet and the distilled water.
A chemical reaction is a change that yields the formation of new substances (products), due to the rearrangements of the atoms of the reactants.
In a very simple form, you can represent a chemical reaction by the general equation:
Which means that some elements or compounds, those in the reactant side of the equation, undergo a change in which some chemical bonds are broken, the atoms separate from the original substances and combine into a new arrangement in which they form one or more different substances (products).
The option B), that the table dissapeared is not a clear evidence of a chemical change because it could have been dissolved, which is a physical change.
Also, the option C), that there was a color change, cannot be cited as an evidence of a chemical reaction, since the color is a physical property.
As for the option D, that there was a change in mass, is not a viable option, since mass cannot change either with a chemical or physical change.
