Try these formulas and then compare your results to those you get on the calculator below: H 2O NH 3 C 2H 4O 2 K 2Cr 2O 7 Molecular Weight Calculatorįormulas can have a max of two brackets open at the same time, and the molecule of crystallization must be placed last.

These calculations will be necessary before one can determine the molarity or normality of a solution and many other formulas in stoichiometry (the quantitative relationships between chemical substances in a chemical equation). (Since the atomic mass average of sulfur given above only has 3 decimal places, accuracy can not be determined beyond that point). In this example the results have been rounded off to the correct number of decimal places.

Add up the results of step three: 2.015+32.066+63.998 = 98.079 = molar mass of sulfuric acid.Multiply each atomic mass by the number of atoms in the formula.Go to periodic table and determine the atomic mass average (atomic weight) of each element.Make a list of each element and the number of atoms of each element present in the substance.The molar mass calculation of a substance is complete the following steps (We will use sulfuric acid, H 2SO 4, as an example):

Once one determines the molar mass of a substance, it will be easy to measure out one mole of that substance. Molar mass is the sum of all of the atomic masses in a formula. Molar massis a unit that enables scientists to calculate the weight of any chemical substance, be it an element or a compound. Since atoms are too small to count, we must weigh out a mole of atoms. It just demonstrates that mole of anything = 6.0221367E 23 and we can measure out a mole of something by counting it or by weighing it out. In order to determine the weight of one mole of bananas, one would have to get an average weight of a banana and multiply that by 6.0221367E 23 then we could weigh out that weight of bananas and presto, we would have a mole of bananas. A mole of any molecule = the molecular mass of that molecule expressed in grams. Since magnesium has an atomic mass of 24, one mole of magnesium weighs 24 grams and contains 6.0221367E 23 atoms of magnesium. It has been established that 1 mole of any element = the atomic mass of that element expressed in grams. Remember, however that 1 mole of carbon-12 = 12 grams = 6.0221367E 23 atoms. Obviously it would be impossible to count out 6.0221367E 23 atoms. (Aren't you glad they don't sell bananas by the mole?) Examples: 1 mole of carbon = 6.0221367E 23 carbon atoms 1 mole of bananas = 6.0221367E 23 bananas One mole of anything, however, contains 6.0221367E 23 of that object. Remember that carbon-12 has an atomic mass of 12 (six neutrons and six protons). By definition, in modern chemistry, one mole represents the number of carbon atoms in exactly 12 grams of carbon 12 isotope. The mole also called mol is the basic unit of measurement in chemistry. In order to grasp the concept of molar mass calculations it is important to understand the molar unit. Skip to site menu on this page Molar Mass Calculations and Molecular Weight Calculator By Roberta Crowell Barbalace.

Mass finder using molarity