Question

What is difference between an ADP molecule and an ATP molecule

Answer 1

ADP = 2 phosphate groups
ATP = 3 phos groups

Answer 2

ADP is adenosine diphosphate, while ATP is adenosine triphosphate. These molecules are related to energy production within a cell, such as the process of cellular respiration. To put it simply, ATP is the energy that powers the cell, while ADP is what is left after the energy is released. Also, like @oOKawaiiOo said, ADP contains two phosphate groups and ATP contains three phosphate groups (hence "diphosphate" and "triphosphate").

Answer 3

ADP has only two phosphate groups while ATP has three.