Answer:
A
Explanation:
this is because density is the mass per unit volume of an object
Answer:

Explanation:
The given reactions are:
PbCl2(aq)⇌Pb2+(aq)+2Cl−(aq) 
AgCl(aq)⇌Ag+(aq)+Cl−(aq) 
Required reaction is:
PbCl2(aq)+2Ag+(aq)⇌2AgCl(aq)+Pb2+(aq)

Nuclear fission is used enable to release energy in power plants. The constant collision of particles within the reactor, create most of the plants energy.