A burning candle gives of heat. This reaction is *
M1

Ithink about 50 % of an original isotope's number of atoms remain

Atp, shorthand for adenosine triphosphate, is the standard molecule for cellular enger in the human body. all motion and metabolic  processes  within the body begins with energy that is released from  atp, as its phosphate bonds are broken in cells through a  process  called hydrolysis.