The unit of length convenient on the atomic scale is known as angstrom and is denoted be Å. The size o a helium atom is about 30 pico meter. What is the total atomic volume in `"metre"^(3)` of one mole of helium atom?

Explanation

`1Å=100pmimplies30pm=0.3Å`
pm `to` picometer `(10^(-12)m)`
`Å=` Angstropm `(10^(-10)`m
Radius of the helium atom `(r)=30pm=0.3Å`
`=0.3xx10^(-10)m`
Volume of helium nucleus
`V=4/3xx3.14xx(0.3xx10^(-10))m^(3)=1.256xx10^(30)m^(3)`
Number of atoms in 1 mole of helium atom
`=` Avogadro's number (N)`=6.023xx10^(23)`
Atomic volume of 1 mole of helium atom (v)
`V'=VxxN`
`V'=Vxxn`
`=1.256xx10^(-30)xx6.023xx10^(23)`
`=7.564xx10^(-7)m`