What global behavior of humans ignores the law of conservation of mass?

Question

I am writing an essay on this...Can anyone give me help?

Answer 1

Nuclear science and Quantum Physics.

E= mc^2 means that mass can be transformed into massless energy, breaking the conservation of mass law.

Answer 2

Very few of human behaviors ignore the law of conservation of mass.  When we burn fossil fuels made up of hydrocarbons by exposing them to oxygen we still maintain the same mass.  It exists as Carbon Dioxide and Water rather than the Hydrocarbon and oxygen.  Even nuclear power plants end up with essentially the same mass in the end products.