1 mol N2 = 2*14 g N2 contains 6.022E23 molecules N2. How many moles N2 do you have?
That's 1.40E23 molecules x (1 mol/6.02E23 molecules) = ?# mols N2.
Then since 1 mol N2 contains 28 g, how much will ?# moles weigh?
find the mass in grams of 1.40x10^23 molecules of n2
6 answers
I really don't understand this problem? Is there a simpler way to do this? Thanks
This IS the simple way.
The basic concept is that 1 mole of anything contains 6.022E23 anythings; i.e., 1 mol N contains 6.022E23 atoms of N, 1 mol N2 contains 6.022E23 molecules of N2, 1 mol of U contains 6.022E23 atoms of U, 1 mol of eggs contains 6.022E23 eggs (that's a lot of eggs).
So you convert molecules you have to mols. You have 1.40E23 molecules and since 1 mol of molecules is 6.02E23 you know this is less than 1 mol. How many mols is this. That's
1.40E23 molecules x (1 mol/6.02E23 molecules) = approx 0.2 mol N2 molecules.
We also know that 1 mol N2 has a mass of 28 (that's 2*14) grams.
So how many grams is approx 0.2 mol.
That's 0.2 mol x (28 g/1 mol) = approx 0.2*28 = ?
Notice that when I multiplied by those "conversion factors" that I always arranged the factors so that the units I had and did not want canceled and the only unit left was what I was converting to. For example, the last one of 0.2 mol x (28g/1 mol) = ?? the mol unit in the numerator cancels with the mol unit in the denominator to leave the unit I am converting to of grams. These are nothing more than converting 1 unit to another unit. First we converted number of molecules to mols, then we converted mols to grams. Isn't chemistry fun? :-). Hang in there. You'll get the hang of it. Don't let chemistry intimidate you. This problem is just two conversions and all of the funny words you aren't used to using are just words. The two conversions are all you need. And all of the conversions work alike. This is really just two math problems with some chemistry words thrown in.
The basic concept is that 1 mole of anything contains 6.022E23 anythings; i.e., 1 mol N contains 6.022E23 atoms of N, 1 mol N2 contains 6.022E23 molecules of N2, 1 mol of U contains 6.022E23 atoms of U, 1 mol of eggs contains 6.022E23 eggs (that's a lot of eggs).
So you convert molecules you have to mols. You have 1.40E23 molecules and since 1 mol of molecules is 6.02E23 you know this is less than 1 mol. How many mols is this. That's
1.40E23 molecules x (1 mol/6.02E23 molecules) = approx 0.2 mol N2 molecules.
We also know that 1 mol N2 has a mass of 28 (that's 2*14) grams.
So how many grams is approx 0.2 mol.
That's 0.2 mol x (28 g/1 mol) = approx 0.2*28 = ?
Notice that when I multiplied by those "conversion factors" that I always arranged the factors so that the units I had and did not want canceled and the only unit left was what I was converting to. For example, the last one of 0.2 mol x (28g/1 mol) = ?? the mol unit in the numerator cancels with the mol unit in the denominator to leave the unit I am converting to of grams. These are nothing more than converting 1 unit to another unit. First we converted number of molecules to mols, then we converted mols to grams. Isn't chemistry fun? :-). Hang in there. You'll get the hang of it. Don't let chemistry intimidate you. This problem is just two conversions and all of the funny words you aren't used to using are just words. The two conversions are all you need. And all of the conversions work alike. This is really just two math problems with some chemistry words thrown in.
I got 5.6
Thanks
Thanks
Did you transpose the numbers? I obtained 6.5 g.
I hate Chem