Question

Based on the information in each choice below, which of the noble gases would have the greatest density for a $1.00L$ sample at room temperature and pressure?

• A. Krypton molar mass $83.8g/mol$, atomic radius $111$ picometers
• B. Argon molar mass $39.9g/mol$, atomic radius $94$ picometers
• C. Neon molar mass $20.2g/mol$, atomic radius $70$ picometers
• D. Helium molar mass $4.0g/mol$, atomic radius $50$ picometers

Answer 1

Answer: (A)

Krypton molar mass $83.8g/mol$, atomic radius $111$ picometers

Ans : A Krypton molar mass $83.3g/mol$, atomic radius III picometers.

Note: [ As we go top to bottom, Atomic mass increases. This is because the $e^{\ominus }$ in bigger noble gases are located away from the nucleus and held less tightly by the atom. Therefore the density of krypton is more then $He,Ne$ and $Ar$].