No, I would not agree with the student's prediction that the chemical reaction between the baking soda and vinegar created new matter.
In a chemical reaction, the atoms and molecules in the reactants are rearranged to form different products, but the total mass of the reactants remains the same. This is known as the Law of Conservation of Mass.
In this specific reaction between baking soda (sodium bicarbonate) and vinegar (acetic acid), carbon dioxide gas is produced, which inflates the balloon. However, the total mass of the reactants (baking soda and vinegar) is the same as the total mass of the products (carbon dioxide gas, water, and sodium acetate).
Therefore, there is no creation of new matter in this chemical reaction, and the total mass at the end of the reaction would be the same as at the beginning.
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