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Chemistry Forums for Students => High School Chemistry Forum => Topic started by: Umbrila on April 12, 2016, 02:55:45 PM

Title: [Solved]How to know the number of hydrogens in saturated hydrocarbon ?
Post by: Umbrila on April 12, 2016, 02:55:45 PM

I have a structural formula and I need to write the amount of hydrogen in each carbon. Its name is 3, 3 - dimethylhexane.

(https://www.chemicalforums.com/proxy.php?request=http%3A%2F%2Fi.imgur.com%2FjO2Ctc2.jpg&hash=1c2f89b2b0663025ed56b19f2c8ba5981bc8a837)

What is the way to find out the amount of hydrogen ? It doesnt seem to have the same amount as just a hexane.

Title: Re: How to know the number of hydrogens in saturated hydrocarbon ?
Post by: mikasaur on April 12, 2016, 03:04:46 PM

How many valence electrons does carbon have? How many bonds do you think it likes to form?

Title: Re: How to know the number of hydrogens in saturated hydrocarbon ?
Post by: AWK on April 12, 2016, 03:50:19 PM

Use general formula for saturated hydrocarbons.

Title: Re: How to know the number of hydrogens in saturated hydrocarbon ?
Post by: Umbrila on April 12, 2016, 04:40:15 PM

4 electrons, so 4 hydrogens ? If I got it right, in the structural formula, from left to right, itll be CH3--CH2--C--CH2--CH2--CH3 ?

Title: Re: How to know the number of hydrogens in saturated hydrocarbon ?
Post by: mikasaur on April 12, 2016, 04:45:44 PM

Yep! Carbon "wants" to form four bonds. That can be from four single bonds, two double bonds, or a single bond and a triple bond.

Your structure is correct (assuming the C in the middle is bonded to the two methyl groups). Good job!

Title: Re: How to know the number of hydrogens in saturated hydrocarbon ?
Post by: Umbrila on April 12, 2016, 04:53:24 PM

Ok, thank you very much !