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1. A hydrocarbon which consists of 82.8 percentage by mass of carbon has an approximate relative molecular mass of 55

What is its empirical formula and molecular formula

Here is my working for empirical

100-82.8=17.82

I divided by the mr and then divided by the smallest number I didn't get the right answer plz help

2. what answer did you get?
3. (Original post by yeah1106)
A hydrocarbon which consists of 82.8 percentage by mass of carbon has an approximate relative molecular mass of 55

What is its empirical formula and molecular formula

Here is my working for empirical

100-82.8=17.82

I divided by the mr and then divided by the smallest number I didn't get the right answer plz help

Posted from TSR Mobile

A hydrocarbon consists of hydrogen and carbon only. If 82.8% of the mass is carbon then what is the percentage mass of hydrogen?
4. Total mass ~ 55
Mr of hydrogen: 1
Mr of carbon: 12

Mass of carbon: 82.8% of 55: 45.54
Mass of hydrogen: 17.2% of 55: 9.46

Moles = mass/Mr
Carbon: 45.54/12 = 3.795
Hydrogen: 9.46(/1)

Ratio of carbon to hydrogen=
3.795 : 9.46
*divide by 3.795*
1 : 2.5
*times by 2*
2 : 5

So empirical formula = C2H5

Posted from TSR Mobile

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