Molecules of hydrogen escape from earth, but molecules of oxygen and nitrogen are held to the surface and remain in the atmosphere. explain

Explanation:

Hydrogen is much lighter than oxygen and nitrogen and therefore can travel faster than both nitrogen and oxygen because of this,  it is able to escape from the the earth and not trapped by the earth Ozone dominated atmosphere.

Hydrogen molecule is lighter in weight than molecules of Oxygen and Nitrogen.

Explanation:The lighter the weight of a gaseous molecule the easier for it to float and overcome the Earth's Gravitational force or pull. Hydrogen molecule is able to escape the Earth's Gravitational pull because of its light or low molecular weight, while Oxygen and Nitrogen are heavier hence they are trapped and prevented from escaping from the Earth's Gravitational pull.

Hydrogen gas molecular weight=2.016g/mol

Oxygen gas molecular weight=16g/mol

Nitrogen molecular weight=28.018g/mol.

vanderwaal's forces of attraction are the electrostatic intermolecular forces that exist in a molecule due to the temporary or permanent dipoles that are developed in a molecule. in , the major intermolecular forces are dipole-dipole interactions as the molecule is polar (bent structure). so the vanderwaal's forces of interaction in between molecules are the permanent dipole-dipole interactions that develop due to the dipole that exists in between the polar h - s bond. the positively charged hydrogen atom is attracted towards the negative end of the dipole that is sulfur of the adjacent molecule. therefore, these forces of attraction are relatively stronger than that of london dispersion forces that exist in non polar molecules.

c. heat could easily travel through the molecules in the air and escape/enter the flask. removing the air slows down the heat transfer.