Question

What is the difference between H2O & D2O?

Answer 1

H2O is the normal water why D2O is the hard water made up of isotope of hydrogen called deuterium

Answer 2

An international collaboration has developed a new technique to explain the true structure of water, and the structural differences between H2O and D2O. ... Using oxygen isotope substitution, Salmon and his team analysed the difference between the O-h and O-D bonds in water molecules.