How many grams of h3po4 are produced when 10.0 moles of water react with an excess of p4o10?
p4o10 +6h2o—> 4hpo4

Explanation:

Hello,

In this case, by considering the given chemical reaction and the molar mass for phosphoric acid and the 4 to 6 relationship between phosphoric acid and water respectively, the required grams are result:

Best regards.

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.