How many double bonds?

Question

How many double bonds in CH2Cl2 and PO4^3-

Answer 1

There are no double bonds in CH₂Cl₂. The hydrogens and chlorines make single bonds to the carbon to fulfill the octet rule for all atoms.

 

As for PO₄^3- the central phosphorous atom makes 3 single bonds to 3 of the oxygens (each of these three has a negative charge to total the -3) and one double bond to the 4th oxygen.