Hn3+cuco3-h2o+co2+cu(no3)2 balance equation

I think you meant HNO3 + CuCO3 ---> H2O + CO2 + Cu(NO3)2. If so, then the balanced equation would be : 2 HNO3 + CuCO3 ---> H2O + CO2 + Cu(NO3)2

the correct option is c.

isotopes refers to different forms of the same element with the same atomic number but different mass number as a result of difference in their neutron numbers. isotopes have different relative atomic mass but share the same chemical properties.