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Topic: limiting reactant  (Read 4088 times)

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Maradona

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limiting reactant
« on: September 20, 2005, 07:41:33 PM »
ok.. i havent been paying attention in class so im a little slow.. but i have a test tommrow, i want to master fundamentals first, so is this right?

using CO + O2 --> CO2, if you started with 120 grams of Carbon monoxide and 100 grams of Oxygen gas, which reactant would run out first?? i did

120g CO ( 1 mol CO/28g CO) ( 1mol CO2/1mol CO) ( 40g CO2/1 mole CO2) = 171.4

100g O2 ( 1mol o2/32g o2)  (1mol co2/1 mol o2) (40 g CO2/1mol O2) = 125

So O2 is the limiting reactant, is this right?

Offline mike

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Re:limiting reactant
« Reply #1 on: September 20, 2005, 08:16:34 PM »
n=m/M

n = number of moles
m = mass
M = molecular weight

CO
m = 120g
M = 28 g.mol-1
so, n = 4.3 mol

O2
m = 100g
M = 32 g.mol-1
so, n = 3.1 mol

So yes O2 is the limiting reagent
There is no science without fancy, and no art without facts.

Offline xiankai

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Re:limiting reactant
« Reply #2 on: September 20, 2005, 08:38:44 PM »
u forgot to balance the equation.
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Offline mike

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Re:limiting reactant
« Reply #3 on: September 20, 2005, 08:42:16 PM »
oops  :-[

xiankai is right, before doing what I did you have to balance the equation, sorry!
There is no science without fancy, and no art without facts.

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