Moles and significance
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Moles and significance
What is the significance of using the measurement of a mole? And when will this unit/information be used?
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Re: Moles and significance
Moles are important because it's a universal standard unit for measuring small things such as atoms or molecules. Moles are used in numerous chemical calculations like calculating molarity (moles of solute/liters of solvent).
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Re: Moles and significance
As Tammy said, a mole is a unit of measurement to measure atoms and molecules which are really small.
An easy way to look at this is to compare a mole to a dozen. We know that a dozen eggs means that there are 12 individual eggs. Similarly when there is a mole of Hydrogen, for example, we know that there are 6.022 × 10^23 hydrogen atoms. So a dozen = 12, while a mole = 6.022x10^23 (which is Avogadro's number).
An easy way to look at this is to compare a mole to a dozen. We know that a dozen eggs means that there are 12 individual eggs. Similarly when there is a mole of Hydrogen, for example, we know that there are 6.022 × 10^23 hydrogen atoms. So a dozen = 12, while a mole = 6.022x10^23 (which is Avogadro's number).
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Re: Moles and significance
Aida Fraser 2I wrote:What is the difference between atomic mass and molar mass of an element?
If you are only talking about an element (for example if you were to talk about H), then they would be exactly the same. 1 mol of H would be 1.007g. *Note: This would be for an atom of H, not for the gas H2. However, if you were to talk about a molecule or ionic compound, atomic mass and molar mass would be different, since atomic mass is the mass of 1 atom of 1 element, while molar mass is the sum of all of the atomic masses in a molecule or ionic compound. Ex. H2 ---> (1.007 x 2)= 2.014
Hope this makes sense!
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Re: Moles and significance
Atomic mass is the sum of both the protons and neutrons in a single atom. This is different from the molar mass— the mass of 1 mole of a substance in grams.
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Re: Moles and significance
Atomic mass is the mass of a SINGLE atom, whereas molar mass is the mass of a mole of a substance.
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Re: Moles and significance
Both the molar mass and atomic mass have the same value for any atom or molecule. Their only difference is in units as molar mass is in grams and atomic mass is in amu.
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Re: Moles and significance
Mole shows the number of atoms of the element you are looking for. You can use it to find the concentration (molarity) of this element, the mass of this element, and so on.
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Re: Moles and significance
Mole is the SI unit for amount of substance. One mole contains exactly 6.022 140 76 x 10^23 elementary entities (generally this number is not used in calculations, you can see it with lower digit). In order to make chemical calculations the amount of substance is required. In addition, mole number of a substance can be used to calculate its mass.
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Re: Moles and significance
Reply to Aida:
The molar mass and atomic mass actually ends up being the same value (numerically), but they refer to slightly different things, with the molar mass being mass of one mole of the substance (unit is g/mol) and atomic mass being of a single atom (unit is amu). The way the conversion works out makes the values exactly the same (since 12 amu is exactly the mass of carbon 12, and avogadros number is the number of carbon 12 atoms in exactly 12 grams).
The molar mass and atomic mass actually ends up being the same value (numerically), but they refer to slightly different things, with the molar mass being mass of one mole of the substance (unit is g/mol) and atomic mass being of a single atom (unit is amu). The way the conversion works out makes the values exactly the same (since 12 amu is exactly the mass of carbon 12, and avogadros number is the number of carbon 12 atoms in exactly 12 grams).
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