What is the answer to this problem

380.5g/mol

Explanation:

The molar mass of a compound can be obtained by adding the molar masses of the elements present in the compound.

The molar mass of Cu3(PO4)2 can be obtained as follow:

Molar Mass of Cu = 63.5g/mol

Molar Mass of P = 31g/mol

Molar Mass of O = 16g/mol

The molar mass of Cu3(PO4)2 = (63.5x3) + 2[31 + (16x4)] = 190.5 + 2[31 + 64] = 190.5 + 2[95] = 190.5 + 190 = 380.5g/mol

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.

the answer is a and have a great day