The+Mole

Mole - measurement not the animal.

The Mole is a measurement.
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A mole contains a certain amount of representative particles, and that is represented by Avogadro's number, (6.02*10^23). A Mole of Oxygen gas, O2 will contain 2(6.02*10^23) oxygen atoms but only 1(6.02*10^23) oxygen gas molecules.
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Avogadro's number links to the atomic mass of any element. A Mole of any element has the exact weight of the atomic mass, but in grams. For example, a mole of H2, hydrogen gas, weighs 2 grams, when Hydrogen's respective atomic mass 1.

When dealing with formulas in measuring mass vs. weight, make sure all atoms are accounted for. For example, Magnesium Hypochlorite, Mg(ClO)2 is calculated as 24.31 + 2( 35.45 + 16 ) which equals 127.21 grams.

When given the weight of any substance, the weight can be used as a numerator, when the representative particles molar weight is used as a denominator, to find just how many moles of said substance you have. For example, when given 20 grams of O2, we then calculate that 20/32 makes our weight to be .625 moles of Oxygen gas. We can then use this number with Avogadro's number to calculate the amount of molecules in the amount given to us, as .625 * (6.02*10^23), which calculates that our measurement of 2 grams of Oxygen gas contains 7.525*10^23 molecules of O2.
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Practice Problems:

1. Describe how Avogadro's number is related to the mole of any substance.

2. Which has more atoms? One mole of Carbon-dioxide or one mole of dihydrogen-monoxide? 3. Calculate the mass of the following 4. Out of the following pairs, which contains more mass?
 * 1 mole of cyanide
 * 3.14159265358 moles of glucose
 * 0.7 mole of Brian (20 kg each)
 * 7 moles of CO2
 * 1 mole of CO2 vs 0.7 mole of glucose
 * 5 moles of ammonium vs 3.5 moles of carbon tetraborate
 * 1 mole of magnesium on earth vs .5 mole of magnesium on Jupiter??

5. Between 1 mole of CO2 and 1 mole of Hydrogen gas, which has more representative particles if a) a representative particle refers to a molecule? b) a representative particle refers to an atom?

6. Brian says that the gram molecular mass for salt (NaCl) is approximately* 57.5 grams. Is Brian's ineptitude and stupidity* shown by his lack of ability* to calculate or use the appropriate terms?


 * Words spelled misspelled by Brad, corrected by Brian.

Solutions

1. One mole of a substance is always equal to Avogadro's number, 6.02*10^23 2. They include the same amount of atoms. 3. 4. 5. a) same b) CO2 6. Unfortunately, Brian is wrong in this instance. However, the fault is not in his mathematical computation, which is accurate beyond compare, but in the incorrect use of his terms. Gram molecular mass is used for molecules, created by covalent bonds, whereas gram formula mass, which would be appropriate for this situation, refers to compounds created with ionic bonds.
 * approx. 26g
 * approx. 396g
 * 8.428*10^24
 * approx. 308g
 * 0.7 mole of glucose
 * 3.5 moles of carbon tetraborate
 * 1 mole of course, lame