Now, you can also easily determine pOH and a concentration of hydroxide ions: Let’s assume that the concentration of hydrogen ions is equal to 0.0001 mol/l. How to calculate pH? - step by step solution Moles must be used because it's a ratio of atoms not a ratio of mass. Typically in the GCSE you use moles to work out the empirical formula of a compound, that is the simplest whole number ratio of atoms of each element in a compound. When we convert to moles we are converting a known mass of an element into a number of atoms so we can use that number to do calculations relating to that reaction. The reason we convert to moles is because one gram of hydrogen doesn't react with one gram of chlorine to make Hydrochloric Acid, but one atom of hydrogen does react with one atom of chlorine to make hydrogen chloride. In 14 grams of nitrogen there are 6x1023 atoms of nitrogen. So, in 12 grams of carbon there are 6x1023 atoms of carbon. It is the number of atoms of an element in a particular mass of that element and it was all based on carbon.

You know that to go from grams to kilograms you multiply by a thousand, well to go from grams to moles you divide by the relative atomic/formula mass from the periodic table.Ī mole, or avagadro's constant is just a number. Does anyone have some sort of resource that can explain to me what the actual hell are moles/molar calculations?Ī mole can be considered to be a unit of measurement, just slightly harder to convert between.

Graphpad prism molarity calculator