Higher density.

Stronger intermolecular forces due to increased mass.

Lower dielectric constant.

Higher viscosity.

Insoluble impurities like silica

Impurities like carbonates and bicarbonates of calcium and magnesium

High density and different physical properties than those of water

The capacity to expedite the rate of nuclear reactions

${C_2}{D_2}$

$Ca{D_2}$

$C{a_2}{D_2}O$

$C{D_2}$

${{\rm{H}}_2}^{18}{\rm{O}}$

${{\rm{D}}_2}{\rm{O}}$

${{\rm{D}}_2}^{18}{\rm{O}}$

${{\rm{H}}_2}{\rm{O}}\;{\rm{ at}}\;4^\circ C$

$100^\circ C$

$101.4^\circ C$

$104^\circ C$

$102.5^\circ C$

Absorbs neutrons efficiently.

Slows down neutrons effectively without absorbing them significantly.

Acts as a coolant by absorbing heat.

Increases the rate of nuclear fission.

$10,{\rm{ }}10,{\rm{ }}10$

$8,{\rm{ }}10,{\rm{ }}11$

$10,{\rm{ }}11,{\rm{ }}10$

$11,{\rm{ }}10,{\rm{ }}10$

${D_2}O$ absorbs neutrons less readily than ${H_2}O$.

${D_2}O$ is cheaper than ${H_2}O$.

${D_2}O$ slows neutrons down more effectively than ${H_2}O$.

${D_2}O$ has a higher boiling point than ${H_2}O$.

$100^\circ C$

$101.4^\circ C$

$104^\circ C$

$102.5^\circ C$

Insoluble impurities like silica

Impurities like carbonates and bicarbonates of calcium and magnesium

High density and different physical properties than those of water

The capacity to expedite the rate of nuclear reactions

${{\rm{C}}_2}{{\rm{D}}_2}$

${\rm{Ca}}{{\rm{D}}_2}$

${\rm{Ca}}{{\rm{D}}_2}{\rm{O}}$

${\rm{C}}{{\rm{D}}_2}$