## Q E27

Emily Orozco L4
Posts: 45
Joined: Fri Sep 28, 2018 12:29 am

### Q E27

Did anyone know how to find part A. I got part B but there's a step I'm missing because I have no idea where the answer from part A comes from.

melodyzaki2E
Posts: 61
Joined: Fri Sep 28, 2018 12:18 am

### Re: Q E27

If you start off with one molecule of water, you have to divide by Avogadro's number to convert the molecule to moles, and then you can multiply the mole by the molar mass of water to get grams. So you should end up with 2.991 x 10^-23 g/molecule. Does that make sense?

Samantha Ito 2E
Posts: 64
Joined: Fri Sep 28, 2018 12:29 am

### Re: Q E27

Since water has a molar mass of 18.02 g/mole, you can divide that by Avogadro's number in order to get g/molecule.
(18.02g/mol)/(6.022*10^23molecules/mol)=2.992*10^-23g/molecule

AustinGrove3B
Posts: 53
Joined: Fri Sep 28, 2018 12:23 am

### Re: Q E27

Find the weight of 1 mole of water. Remember each mole of a substance contains exactly 6.022*10^23 molecules of that substance. Therefore the weight of a mole of water divided by 6.022*10^23 would equal the weight of 1 water molecule.

005113695
Posts: 59
Joined: Fri Sep 28, 2018 12:15 am

### Re: Q E27

To find the mass of one water molecule, divide it by Avogadro's number and then multiply it by the molar mass of water.