Question 5 (4 points)

a reaction begins with 15 grams of reactants. how many grams of product will in the

new substance after the reaction?

Explanation:

According to law of conservation of mass, mass can neither be created nor it can be destroyed. It can only be changed from one form to another.

Therefore, when 15 grams of reactants will combine together to result in the formation of a new compound then mass of the new substance formed will also be 15 grams.

Because, mass of reactants has converted into the mass of product.

Thus, we can conclude that 15 grams of product will in the  new substance after the reaction.

answer is: c. the experiment shows that the red substance experienced a chemical change.

this is chemical change (chemical reaction), because two new substances are formed (metalig liquid and gas), the atoms are rearranged and the reaction is followed by an energy change.

this is example of chemical decomposition.

chemical decomposition (analysis) is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds.  

chemical decomposition is opposite of chemical synthesis.