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Leoragon
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Can someone explain to me these two things? I'm trying to get the average mass of air and it says it is 29g/mol? But what is a mole? I know it's the amount of carbon-12 atoms in 12 grams. What does 12 grams look like?
Leoragon said:I'm still confused. I'm only 13 and I'm like "huh?"
RedSonja said:The mol is defined from the massunit "units", which is defined as [itex]\frac{1}{12}[/itex] of the mass of a carbon-12 atom
Borek said:Mol is not defined in mass units.
Leoragon said:Okay, well in the average molar mass (is that what you call it?)
the mass is 29 grams for every mole amount of air molecules.
So to get the mass of a single molecule in a molecule, you divide the mass by a mole? So 29/(6.0221415 X 10^23) = 4.81 X 10^-23 [appoximately]. Is that correct?
Borek said:You just have to remember this is an average mass, so there is no single molecule of this mass in the real air...
A mole (mol) is a unit of measurement used in chemistry to express the amount of a substance. It is defined as the amount of a substance that contains the same number of particles (atoms, molecules, or ions) as there are in 12 grams of carbon-12. This number is approximately 6.022 x 10^23 particles, also known as Avogadro's number.
A mole (mol) is a unit of measurement for the amount of a substance, while a gram (g) is a unit of measurement for mass. A mole is used to express the number of particles, while a gram is used to express the weight or mass of those particles. One mole of a substance will have a different mass in grams depending on the substance's molecular weight.
Molar mass (g/mol) is the mass of one mole of a substance. It is calculated by multiplying the atomic weight of each element in the substance by the number of atoms present and then adding all of these values together. This means that the molar mass of a substance is equal to its mass in grams per mole (g/mol).
A mole (mol) is used in chemical equations as a conversion factor. It allows us to relate the number of moles of a substance to the number of particles or the mass of that substance. This is important because chemical reactions occur between particles, and these particles are measured in moles.
For example, to calculate the number of moles in 25 grams of water (H2O), we would first determine the molar mass of water, which is 18.02 g/mol. Then, we would use the formula: moles = mass/molar mass. In this case, it would be 25 g/18.02 g/mol = 1.39 mol. To calculate the molar mass of a substance, we would use the same formula but rearranged to solve for molar mass: molar mass = mass/moles. So, the molar mass of water would be 25 g/1.39 mol = 18.02 g/mol.