Formula Units?

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Isabel Nakoud 4D
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Formula Units?

Postby Isabel Nakoud 4D » Sat Oct 06, 2018 1:01 pm

A problem in the book asked, "How many formula units of the compound are present in 5.15 g of Magnesium Sulfate Heptahydrate?"

What are "formula units"?

Sydney Aurelio_Dis4B
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Joined: Fri Sep 28, 2018 12:28 am

Re: Formula Units?

Postby Sydney Aurelio_Dis4B » Sat Oct 06, 2018 1:10 pm

I believe formula units would be the amount of moles of that compound, multiplied by Avogadro's number

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Re: Formula Units?

Postby Javier_Ochoa_DIS_3J » Sat Oct 06, 2018 1:38 pm

Formula units is the atoms I believe.

First you have to get the moles of the element(s), To get this you have to use the given grams and divide it by the total molar mass found on the periodic table.

You would multiply the moles with 6.0221409e+23 (Avogadro constant) to find out how many atoms or formula units you would have.

Kelsey Li 3B
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Joined: Fri Sep 28, 2018 12:26 am

Re: Formula Units?

Postby Kelsey Li 3B » Sat Oct 06, 2018 1:58 pm

Formula units refer to the concept that one mole contains the Avogadro's number of any units. This means that one moles is equal to 6.022*10^23 formula units which is also equivalent to 6.022*10^23 molecules. Formula units just refer to ionic compounds while molecules refer to molecular compounds. Hope this helps!

Asia Yamada 2B
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Re: Formula Units?

Postby Asia Yamada 2B » Wed Oct 07, 2020 2:29 am

A mole of an ionic compound corresponds to 6.02x10^23 formula units. To find the amount of formula units in 5.15g of Magnesium Sulfate Heptahydrate, you divide by the molar mass of this compound, then multiply by Avogadro’s number.

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Re: Formula Units?

Postby OwenSumter_2F » Wed Oct 07, 2020 9:11 am

Formula units are the term for ionic compounds, such as molecules for a regular compound or atoms for atoms.

Brandon Le 3C
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Re: Formula Units?

Postby Brandon Le 3C » Wed Oct 07, 2020 11:30 am

In order to find how many formula units are in a given compound, you must first divide the amount of a sample by its molar mass to convert the mass to moles. Then, multiply this value by Avogadro's constant, 6.022 * 10^23, to find how many formula units are present in the given sample.

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