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Chemistry help (1 Viewer)

FCB

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A 5.00 gr of a unknown compound contains 1.86g C, .39g H and 2.75g of Cl. Write the empirical formula

I tried dividing the 1.86/0.39 but it came out with 4.7....
I thought this might give me the ratio but it hasn't helped
 

hscishard

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A 5.00 gr of a unknown compound contains 1.86g C, .39g H and 2.75g of Cl. Write the empirical formula

I tried dividing the 1.86/0.39 but it came out with 4.7....
I thought this might give me the ratio but it hasn't helped
Think you needa find how many carbon atoms there are in 1.86g of Carbon, how many hydrogen atoms in .39g, etc
Then it would be no.carbon no. of hydrogen and no. of chlroine...Then simplify the ratio.

What module is this?
 

chrisnumber1

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Think you needa find how many carbon atoms there are in 1.86g of Carbon, how many hydrogen atoms in .39g, etc
Then it would be no.carbon no. of hydrogen and no. of chlroine...Then simplify the ratio.

What module is this?
you would use moles instead of atoms but yeah your on the right track. there basically the same thing
 

zxreth

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find the percentage composition and then work from there.
 

namesAsh

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Firstly set it out in ratio form, there's nothing new here just what we know already

1.86 C : 0.39 H : 2.75 Cl

From here we want to get the atomic mass of the element and divide it into said element, eg; 1.86 divided by 12.01 = 0.15 (2dp)

0.15 : 0.39 : 0.08
(These are the answers I got with my periodic table, yours may be different)

From here we divide the lowest number from this set of numbers into the others to get the ratios, you may also find it that you won't nice whole numbers but don't worry round it up.

2 : 5 : 1

That's it!

Empirical formula is C2H5Cl
 

Icee_tee

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C2H5Cl

I think this might be right.
Check it and tell me if i got it right or not.
ty
 

FCB

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That seems right to me.

Thanks
 

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