What volume will 5.1*1022 atoms of ne occupy at stp?

First let us calculate the number of moles of Ne using Avogadros number.

number of moles = 5.1*10^22 atoms * (1 mole / 6.022x10^23 atoms)

number of moles = 0.08469 mole

At STP, a gas would occupy 22.4L/mole

V = (22.4L/mole) * 0.08469 mole

V = 1.90 L