Question

Which of the following is incorrect?

• A. $\text{Hydrogen > Deuterium > Tritium}$
  (% relative abundance)
• B. $\text{Hydrogen > Deuterium > Tritium}$
  (Melting point)
• C. $\text{Hydrogen < Deuterium <Tritium}$
  (Boiling point)
• D. $\text{Hydrogen < Deuterium <Tritium}$
  (Dissociation energy)

Answer 1

The correct option is B $\text{Hydrogen > Deuterium > Tritium}$

(Melting point)
Melting point order for the isotopes of hydrogen is as follows:
$\underset{13.90K}{\text{Hydrogen}}<\underset{18.50K}{\text{Deuterium}}<\underset{20.60K}{\text{Tritium}}$
Hence, (b) is incorrect.