Hey everyone,(adsbygoogle = window.adsbygoogle || []).push({});

I have this problem to solve:

A hydrocarbon (CxHy) contains 92.3% of Carbon and 7.7% of Hydrogen.

1) What is its molar mass, if the density of its smoke to the air is d=2.69 ?

92.3/7.7 = 12

So 12x=y

This is the first equation. I have to find a second one to find what is x and what is y, in order to find the molar mass of CxHy.

Is the density of water to the air can be written as d=(molar mass of the compound)/(molar mass of the water) ???

Anyhelp/hints would be appreciated.

Mohammed

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# Homework Help: Molar mass

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