Could someone pls help me out with this q? T^T
I don't understand the mark scheme
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Chem unit 1 q watch
- 22-02-2018 10:33
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- 25-02-2018 09:50
it's asking you to find kJ per kg.
It gives you kJ per mol, and g per mol. Note that kg = 1000g.
So dividing kJ per mol by g per mol, the mol cancels to leave you kJ per g. But remember, you want kJ per kg.
You must then multiply this by 1000 (but more intuitively, you are dividing 170g by 1000 to get it into kilograms, then as this 1000 is on the denominator being divided by law of fractions it comes to the top as a multiple.
- 25-02-2018 13:43
Oh we had to consider the units. I was looking for a formula >< Thank you!