00:02
Okay, so we're asked to solve how many grams of nickel chloride is in 2 .56 moles of nickel chloride.
00:10
And so we're converting a mass unit that we can measure from on a scale.
00:16
We're trying to find how many grams, something we measure on a scale from 2 .56 moles.
00:21
The moles are kind of like the baker's dozen of chemistry, where it allows us to perform reactions and stuff very easily.
00:31
Moles, but you can't, there isn't a scale that measures moles.
00:34
Everything measures in grams or pounds if you get one of those scales.
00:41
But usually it's in grams.
00:42
And so we need a weight to convert between moles and grams and back and forth.
00:46
And so what that conversion value is going to be is molecular weight or molecular mass.
00:53
People refer to it as both.
00:56
Both are correct.
00:58
And so what this number is it's a conversion factor that allows us to go back and forth between these two units.
01:05
And how we find this number is one of several ways.
01:08
One, you could just google it online if you have access to that during your exam or assignment or whatever, but usually at this stage, they're asking you to solve for it.
01:18
And so if you refer to the prrq table, you'll notice several numbers.
01:22
Like if we're looking at the box versus a hydrogen, usually as a one, that's the atomic number, and usually below that it's some number.
01:30
The number of decimal points afterwards.
01:32
And this is the molecular weight of that element.
01:39
So we had a mole of hydrogen, it weighed 1 .001 grams.
01:43
And so every element has a number just like that.
01:46
And so for nickel, once you find on that pair of table, you'd find that number to be 58 .693 grams...