Calculating number of moles of an element

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Emilie_Paltrinieri_1K
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Calculating number of moles of an element

Postby Emilie_Paltrinieri_1K » Sun Oct 11, 2020 7:15 am

When calculating the number of moles of an element we always use 100g. I was wondering if we use 100g just for semplicity, and if there is any particular case where we should consider different quantities.

Quentin Scarborough 1A
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Re: Calculating number of moles of an element

Postby Quentin Scarborough 1A » Sun Oct 11, 2020 9:03 am

We use 100g simply because it is easier to visualize the mass percentage composition. You could use other values but it would make it more difficult. It just depends on the method that works best for you.

Chenning Yang Dis3l
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Joined: Fri Oct 09, 2020 12:16 am

Re: Calculating number of moles of an element

Postby Chenning Yang Dis3l » Sun Oct 11, 2020 9:18 am

I think 100g works the best for most cases since it makes the numbers much simpler.

305392242
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Joined: Wed Sep 30, 2020 9:47 pm

Re: Calculating number of moles of an element

Postby 305392242 » Sun Oct 11, 2020 11:09 am

100g is a tool to help conceptualize the elemental proportions of a molecule to equal 100%. It's an arbitrary number that always works in those problems.

Sachi Sengupta 3B
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Joined: Wed Sep 30, 2020 9:49 pm

Re: Calculating number of moles of an element

Postby Sachi Sengupta 3B » Sun Oct 11, 2020 11:13 am

You're completely right! We use 100g for simplicity since we are usually given the mass percent composition and that way it an easy conversion from percent to grams of the element.

Claudia_Danysh_2C
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Re: Calculating number of moles of an element

Postby Claudia_Danysh_2C » Sun Oct 11, 2020 3:48 pm

I also think that we pretend we have 100 grams in total because it makes the calculations easier because when you're first learning how to figure out empirical and molecular formulas, pretending that there are 100 grams in total just makes it easier to approach each problem since you start each problem the same way!

Emma_Barrall_1D
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Joined: Wed Sep 30, 2020 9:55 pm

Re: Calculating number of moles of an element

Postby Emma_Barrall_1D » Sun Oct 11, 2020 4:17 pm

Assuming 100g for percent composition just helps with simplicity!

Thomas Gimeno
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Re: Calculating number of moles of an element

Postby Thomas Gimeno » Sun Oct 18, 2020 10:19 pm

It 100% for simplicity. When you have 45% of something, its a lot easier to just write it as 45g then as an obscure number representing a different total

905389581
Posts: 39
Joined: Wed Sep 30, 2020 10:11 pm

Re: Calculating number of moles of an element

Postby 905389581 » Sun Oct 18, 2020 10:20 pm

Yea im pretty sure we use it just to make the calculations simpler!

Bai Rong Lin 3I
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Joined: Wed Sep 30, 2020 9:54 pm

Re: Calculating number of moles of an element

Postby Bai Rong Lin 3I » Sun Oct 18, 2020 11:24 pm

Emilie_Paltrinieri_1K wrote:When calculating the number of moles of an element we always use 100g. I was wondering if we use 100g just for semplicity, and if there is any particular case where we should consider different quantities.

I believe it is cause 100g is much easier for simplification, and also it was one of the things I was first taught with and more used to using!

Edward Castro
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Joined: Wed Sep 30, 2020 9:32 pm

Re: Calculating number of moles of an element

Postby Edward Castro » Sun Oct 18, 2020 11:32 pm

100g is the best way to make sure you get the best simplifying answer for your problem. This method will help you fly by your problems and make it easier to solve.


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