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Maddy1012

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i have no idea what to do for this question...

a mass of 72.5g of ethanol was brnt completely in ar. Calculate the volume of C02 that wasproduced at 25 degrees celcius at 100kPa.

:)
 

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Maddy1012 said:
i have no idea what to do for this question...

a mass of 72.5g of ethanol was brnt completely in ar. Calculate the volume of C02 that wasproduced at 25 degrees celcius at 100kPa.

:)
Write your EQUATION (always always always do this when you can), oh and assume it completely burns up (enough or excess oxygen)

C2H5OH (l) + 3O2 (g) ---> 3H2O + 2CO2


Convert the mass of ETHANOL to MOLES

72.5g/46g = 1.58 (to 2 decimal places)

(Because 46g of Ethanol is 1 MOLE.)



1M of ANY gas occupies 24.71 L @ 25 degrees AND 100kPa
(This 24.71L may vary with different textbooks.)

BUT

1 MOLE
C2H5OH makes 2 MOLES of CO2, but you have 1.58 MOLES

So we MULTIPLY the 1.58 by 2 = 5.16M


5.16 x 24.71 = 127.5L (to 1 decimal place)



OUR STATEMENT:

5.16M of CO2 gas occupies 127.5L @ 25 degrees AND 100kPa
 

Maddy1012

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1.58 times 2 isnt 5.16... but i get the drift... thankyou so so very much:wave:
 

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