Explanation: Concentration is defined as the amount of solute dissolved in a known amount of the solvent or a solution.
Parts per million (ppm) is used to express the concentration when a very small quantity of solute is present in a large quantity of the solution. It is defined as the mass of solute present in one milion parts by mass of the solution.
Also to clarify further, L/s is a unit of flow rate, J/g is a unit of energy per unit mass, and kPa is a unit of pressure known as kilo pascals which is equivalent to 1000 pascals
so you can see those fluorine atoms have really spread out around the central phosphorus atom. this gives us a trigonal bi-pyramidal molecular geometry for pf5.