Answer:Physical
Explanation:
State Change is physical because it changes without it being chemically done. So when water changes from a liquid to a solid the state of it is changing. (Solid or Liquid or Gas)
Basically what is physically being changed with out a chemical.
Answer:
Cu + 4HNO3 ---> Cu(NO3)2 + 2NO2 + 2H2O.
Explanation:
Balancing:
Cu + 4HNO3 ---> Cu(NO3)2 + 2 NO2 + 2H2O.