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What is the molar mass of Helium?

Bess Ruff, MA
Environmental Scientist
Bess Ruff is a Geography PhD student at Florida State University. She received her MA in Environmental Science and Management from the University of California, Santa Barbara in 2016. She has conducted survey work for marine spatial planning projects in the Caribbean and provided research support as a graduate fellow for the Sustainable Fisheries Group.

Bess Ruff, MA

Environmental Scientist

Expert Answer

4.002602 g/mol; you might find that some periodic tables will round this number to 4.00

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What is the molecular mass of oxygen and hydrogen as a mixture?

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Oxygen with Hydrogen gives you WATER (H2O). The relative atomic mass for Oxygen is 16, while Hydrogen is 1 since Hydrogen (H2) have two molecules you multiply by 2 1*2=2. Oxygen (O) being 16*1=16. Add up your answers to get 18, and the molecular mass of Oxygen and Hydrogen which is water gives you 18.

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How do you calculate the molar mass of water?

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Water's chemical formula is H2O, this means it is composed of 2 Hydrogen atoms and 1 Oxygen atom. To find the molar mass, find the atomic mass of all the components of a chemical. You can either memorize it, or find all of the atomic masses located on the periodic table of elements. In this case, hydrogen has an atomic mass of 1, and oxygen has an atomic mass of 16. The equation is therefore: 1(2) + 16(1) = 18. Therefore, the molar mass of water, is 18.

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How do I identify the element when you are given the mass in grams and the mass of moles?

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Divide the mass in grams by the number of moles to get the atomic mass. Then refer to the Periodic Table of Elements to identify the element.

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What is the difference between molar mass and molecular weight?

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In practice, nothing, but they have different units of measurement. Molecular weight is the mass of one molecule (atomic mass units) while molar mass is the weight of a mole of molecules (grams per mole).

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How can I calculate the molar mass if only the atomic weight is given?

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You can't perform the necessary calculations without knowledge of either how many moles are in the formula or what elements are used.

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How many grams are there in 0.75 moles of glucose?

Community Answer

Glucose: C6H12O6. At first, you should find its formula mass which is around 180.014 g/mol and then you multiply it by the moles of glucose you have, which is 0.75, and the result is 135.01 g.

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How do I calculate the molar mass of methane gas?

Community Answer

Formula of methane is CH4. We know that molar mass of carbon is 12, and molar mass of hydrogen is 1. Therefore, molar mass of CH4 is equal to 12 + 1 x 4, or 12 + 4, which equals 16.

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What number of atoms are present in 20 grams of HBr?

Community Answer

Use formula n=N/NA (then N=n*NA) where N is number of atoms and NA is the Avogadro's constant which is 6,023x10^23. You can calculate 'n' via m/M in which M applies to molar mass of HBr, which is 1+80.

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How can I calculate the content of Copper in Copper Gluconate?

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By taking the molar mass of each one of them and subtracting the molar mass of Copper from what they give all together.

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What is the molecular mass of aluminium?

Thu NGUYEN

Community Answer

The relative atomic mass of Al is 26.981, thus its molar mass is 26.981.

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What is the molar mass of hydrogen?

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Refer to the atomic mass of hydrogen on the periodic table (1.007). 1.007 * 1g/mol = 1.007 g/mol.

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How do I calculate the mass in grams of 55 moles of Na atoms?

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Mass=molecular mass x moles. So mm*n=M (molecular mass [mm] can be found with a periodic table), gives you 22.99*55 = 1264.45 g

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What is the molar mass of 2.5 g of an unknown sample dissolved in 130 mL of water with a concentration of 0.480M?

Community Answer

To find the Molar mass in a solution, the formula n=CV is used (where n=# of Moles, C= concentration in mol/L, V=Volume (L)) to calculate how many moles of the substance are in the solution. n=0.48x0.13, n=0.0624. With the number of moles established (0.0624 mol) the equation n=m/mm can be rearranged to make mm=m/n (where mm= Molar mass (g/mol), m=mass (g), n=#of moles (mol)). mm=2.5/0.0624, mm=40.064 g/mol. So 40.064 g/mol is the molecular mass of the unknown substance.

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How do I calculate the molar mass from 5.42 g and 0.0416 moles?

Community Answer

Do the math. We know that the equation is n=m/M (where n is the number of moles, m is mass, and M is molar mass). Using algebra, we change the equation to M=m/n where if we replace your number we get M=5.42/0.0416, M=130.29 (2 d.p).

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How do you get the molecular mass for 8H2O?

Community Answer

Simple, you get the molecular mass of H2O i.e 18. Then you multiply it with 8. Which is 144.

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Is there an element that has eighty-eight as its molar mess?

Community Answer

The closest to your answer is strontium(Sr), which has a molar mass of 87.6.

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