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Topic: Double bond equivalent question  (Read 24144 times)

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Offline mass

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Double bond equivalent question
« on: April 16, 2008, 07:18:46 AM »
According to my notes the formula to calculate a DBE is = (c+1) - (H* - N)/2

I applied this forumla in order to calculate the number of double bond equivalents for the molecle C6H1206.

So = 6+1 - (12)/2

However, according to the textbook the answer is meant to be 1 but the answer I get using the formula is different.

Offline Arkcon

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Re: Double bond equivalent question
« Reply #1 on: April 16, 2008, 07:31:31 AM »
According to my notes the formula to calculate a DBE is = (c+1) - (H* - N)/2

I applied this forumla in order to calculate the number of double bond equivalents for the molecle C6H1206.

So = 6+1 - (12)/2

However, according to the textbook the answer is meant to be 1 but the answer I get using the formula is different.

Ummm...the result of your formula above is, in fact, 1.  What do you get?
Hey, I'm not judging.  I just like to shoot straight.  I'm a man of science.

Offline mass

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Re: Double bond equivalent question
« Reply #2 on: April 16, 2008, 10:33:28 AM »
how can it be 7-12 = -5 and then divided by 2 = -2.5.

Offline sjb

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Re: Double bond equivalent question
« Reply #3 on: April 16, 2008, 10:40:54 AM »
Instead of (6+1-12) / 2, look at the formula again. It should be 6+1 - 12/2 = 1.

Remember division and multiplication have higher priority than addition and subraction.

(This is one of those times I wish I spoke LaTex better)

S

Offline mass

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Re: Double bond equivalent question
« Reply #4 on: April 16, 2008, 11:22:01 AM »
Instead of (6+1-12) / 2, look at the formula again. It should be 6+1 - 12/2 = 1.

Remember division and multiplication have higher priority than addition and subraction.

(This is one of those times I wish I spoke LaTex better)

S

oh yes, simple rules of maths. Thanks again sjb, you are a star.

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