March 29, 2015

Homework Help: Chemistry Please HELP

Posted by Saira on Thursday, October 23, 2008 at 7:00pm.

A 1.082 g sample of a component of the light petroleum distillate called naptha is found to yield 3.317 g CO2 and 1.584 g H2O on complete combustion

This particular compound is also found to be an alkane with one methyl group attached to a longer carbon chain and to have a molecular formula twice its empirical formula

The compound also has the following properties:

melting point: -154 C
boiling point: 60.3 C
density: 0.6532 g/mL at 20.0 C
specific heat: 2.25 J
DeltaH f = -204.6 kJ/mol

Use the masses of CO2 and H2O to determine the empirical formula of the alkane component.


First i calculated the number of moles of Carbon and Hydrogen present in the unknown:

Molar mass = 43.99
CO2 mass - 3.317 g

moles= 0.0754
Molar mass: 18.01
Mass of H20- 1.584 g

moles = 0.08795

Since there are 2 hydrogens in H2O
the moles are 0.01760.

And then i divide the moles by the lowest number:

Carbon: 0.0754/ 0.0754 = 1
Hydrogen: 0.0879/ 0.0754 = 1.16

I am not sure what to do next...

Answer this Question

First Name:
School Subject:

Related Questions

Chemistry - A compound containing only carbon, hydrogen and oxygen is subjected ...
Chemistry - A compound contains only carbon, hydrogen, nitrogen, and oxygen. ...
Chemistry - A compound containing only C, H, and N yields the following data. (i...
Chemistry PLEASE HELP! - A compound is known to contain only C, H, and N. On...
Chemistry - a compound was analyzed and found to contain C,H,N,O, and Cl. When o...
Chemistry - Hi, I posted a question yesterday : A compound contains only carbon...
chemistry - Upon combustion, 4.30 grams sample of a compound containing only ...
chemistry - last one, i PROMISE A compound containing only C, H, O and Cr was ...
chemistry - An unidentified compound (A) was reacted with bleach using the same ...
chemistry - An orgnaic compound contains C, H, No, and O. Combustion of 0.1023 g...