Molar Mass

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Kallista McCarty 1C
Posts: 212
Joined: Wed Sep 18, 2019 12:18 am

Molar Mass

Postby Kallista McCarty 1C » Mon Oct 07, 2019 10:38 pm

What is the molar mass of a sample if a single molecule weights 5.34 x 10^3 g? How do you find the answer to this?

Qiu Ya Wu 4I
Posts: 107
Joined: Fri Sep 20, 2019 12:17 am

Re: Molar Mass

Postby Qiu Ya Wu 4I » Mon Oct 07, 2019 10:42 pm

Perhaps you could multiply the molecule's weight by Avogadro's number to find the mass for 1 mole of that particular molecule. Doing should give you the molar mass of the molecule.

JasonLiu_2J
Posts: 109
Joined: Sat Aug 24, 2019 12:17 am

Re: Molar Mass

Postby JasonLiu_2J » Mon Oct 07, 2019 10:43 pm

You can think of the mass as being 5.34 x 10^3 g per one molecule. Since the molar mass of a sample is in units of grams/mole, you would need to convert the mass you have from grams/molecule to grams/mole. To do this, you would want to multiple the given mass of 5.34 x 10^3 grams/molecule by Avogadro's number (6.022 x 10^23 molecules per mole). The units of "molecules" would cancel out and leave you with the units of grams/mole. In summary, to find the molar mass you would multiply the given mass by Avogadro's number, which will give you the mass per mole of the sample.

britthanul234
Posts: 51
Joined: Wed Sep 18, 2019 12:21 am

Re: Molar Mass

Postby britthanul234 » Tue Oct 08, 2019 4:56 pm

You just have to use Avogadro's number since the question gives you the weight of the single molecule. Molecule should be a key word that allows you to realize that you should be using Avogadro's number and doing a bunch of various conversions.

Grecia Velasco 4D
Posts: 56
Joined: Thu Jul 11, 2019 12:17 am

Re: Molar Mass

Postby Grecia Velasco 4D » Wed Oct 09, 2019 12:22 pm

Molar mass = Grams/avogadro's constant, so just divide the grams of element given by 6.022x10^23 to find the molar mass.

n=m/Na

thanh24mai
Posts: 50
Joined: Thu Jul 25, 2019 12:17 am

Re: Molar Mass

Postby thanh24mai » Wed Oct 09, 2019 11:16 pm

the word molecule hints that you need to use Avogadro's number !

Michelle Le 1J
Posts: 50
Joined: Fri Aug 09, 2019 12:16 am

Re: Molar Mass

Postby Michelle Le 1J » Wed Oct 09, 2019 11:21 pm

You can always use Avogadro's number to convert between atoms, molecules, and (molar mass) grams.

sarahsalama2E
Posts: 164
Joined: Fri Aug 30, 2019 12:16 am

Re: Molar Mass

Postby sarahsalama2E » Wed Oct 09, 2019 11:57 pm

keyword: molecules

because molecules is mentioned, we can use avogadros number which is 6.023 x 10^23 to convert to molar mass. Using dimensional analysis we can cancel out the molecules when we multiple the given grams by avogadros number--> this gives us the molar mass of the sample.


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