A couple of the ideas we've discussed in this class have been the moles and molar ratios. A mole is just a unit of a number of atoms--more precisely, 1 mol (the somewhat pointless abbreviation for mole) is approximately equal to 6.02x10^23 atoms. Having this unit of measurement is nice because it allows us to convert different substances into units that can be solved for. Let's do some molar calculations to see how this can be applied.
Let's try to answer this problem: How many moles are in 37 grams of copper?
This question is easy enough to answer. The molar weight (as given on a periodic table) of copper is about 63.54 (1 mole weighs about 63.54 g). Dividing, this shows us that 37 g is about .58 mols.
Now, let's move on to a more advanced problem. What if I asked how many atoms were in 37 g of copper?
It's probably easiest, at this point, to use a visual aid to find the solution for this problem.
Looking at this, we can see that the units, in essence "cancel out," leaving behind atoms Cu. Solving, we can see that this gives us about 3.49x10^23 atoms.
We'll do several more problems with this technique throughout the course of this blog.
Let's try to answer this problem: How many moles are in 37 grams of copper?
This question is easy enough to answer. The molar weight (as given on a periodic table) of copper is about 63.54 (1 mole weighs about 63.54 g). Dividing, this shows us that 37 g is about .58 mols.
Now, let's move on to a more advanced problem. What if I asked how many atoms were in 37 g of copper?
It's probably easiest, at this point, to use a visual aid to find the solution for this problem.
| 37 g Cu | 1 mol Cu | 6.02x10^23 atoms Cu |
| 63.54 g Cu | 1 mol Cu |
Looking at this, we can see that the units, in essence "cancel out," leaving behind atoms Cu. Solving, we can see that this gives us about 3.49x10^23 atoms.
We'll do several more problems with this technique throughout the course of this blog.
No comments:
Post a Comment