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jennijam1
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Joined: Wed May 02, 2012 8:01 am

Homework help

Post by jennijam1 »

Calculate the mass of carbon dioxide produced from 22.6 g of octane, C8H18, in the following reaction. 2C8H18(g) + 25O2(g) --> 16CO2(g) + 18H2O (g)
KriggY
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Location: Olomouc - Czech Republic

Post by KriggY »

69.8 grams

you have 22.6 / (8*12 + 18 ) = 0.198 moles of C8H18 and from the equation the amount of moles of CO2 is 8times higher so in the end you have
8 * 0.198 moles of CO2 which is 1.58 mole.
1.58 * (12+32) = 69.8g
GrahamKemp
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Answer: 69.7 g

Post by GrahamKemp »

In general:

:!:

Code: Select all

Mp = (Np * Wp * Mr) / (Nr * Wr)

Where
Mp : Mass of Product (CO2)
Wp : Atomic-Weight of Product = 44.009 g/mole
Np : Stocimetric Number of Product (ie. moles in the equation) = 16
Mr : Mass of Reactant (C8H18) = 22.6 g
Wr : Atomic-Weight of Reactant = 114.23 g/mole
Nr : Stocimetric Number of Reactant = 2

:arrow: Mp = 69.656 g
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