Knowing the viscosity coefficient of helium under standard conditions, calculate the effective diameter of the helium atom.

Calculate the Effective nuclear charge of helium.

The heat conductivity of helium is 8.7 times that of argon (under standard conditions). Find the radio of effective diameters of argon and helium atoms.

Calculate the number of atoms in 1g of helium

Calculate the rms speed of helium atoms at 127^(@) C .

The two electrons in helium atom

The two electrons in helium atom