Which inert gas is lightest?

Which one is the lightest —

Which one is lightest and which one is heaviest of all the metals?

The elements A, B and C have atomic numbers Z -2, Z and Z +1 respecively. Of the three, B is an inert gas. Which one has the highest value of ionisation potential?

The elements A, B and C have atomic numbers Z -2, Z and Z +1 respecively. Of the three, B is an inert gas. Which one has the highest value of electronegativity?

Which is the lightest gas know?

Which is the lightest among the following?

The atomic number of the inert gas in which the total number of d-electrons is equal to the difference in the numbers of total p-and s-electrons is-

Which of the following is the lightest metal ?

The inert gas having the highest ionization potential is