Number of moles is found by formula n=mass/molar mass, or m/M. the molar mass is found by adding together the atomic masses of Na and Cl (22.99 + 35.45) to give 58.44 g/mol. Since the mass of NaCl is 75.0g, we find the number of moles as follows:
n = 75.0 / 58.44 = 1.28 mol
<span> Atoms and Molecules Matter is made up of tiny particles called atoms and molecules.</span>
Answer:
Increasing London dispersion forces
Explanation:
The graph below shows that the boiling points increase smoothly as you go from CH₄ to PbH₄, that is, as the molecular mass increases.
The only intermolecular forces between the molecules are London dispersion forces.
These forces increase with increasing molecular mass because there more electrons that can be temporarily on one side of the molecule to induce a temporary dipole in a nearby molecule.