Answer:
The limiting reacting is O2
Explanation:
Step 1: data given
Number of moles O2 = 21 moles
Number of moles C6H6O = 4.0 moles
Step 2: The balanced equation
C6H6O + 7O2 → 6CO2 + 3H2O
Step 3: Calculate the limiting reactant
For 1 mol C6H6O we need 7 moles O2 to produce 6 moles CO2 and 3 moles H2O
O2 is the limiting reactant. It will completely be consumed (21 moles).
C6H6O is in excess.
For 7 moles O2 we need 1 mol C6H6O
For 21 moles O2 we'll need 21/7 = 3 moles C6H6O
There will remain 4.0 - 3.0 = 1 mol C6H6O
Step 4: calculate products
For 1 mol C6H6O we need 7 moles O2 to produce 6 moles CO2 and 3 moles H2O
For 21 moles O2 we'll have 6/7 * 21 = 18 moles CO2
For 21 moles O2 we'll have 3/7 * 21 = 9 moles H2O
The limiting reacting is O2
Molar mass
H2S = 34.0 g/mol
O2 = 31.99 g/mol
S8 = 256.52 g/mol
Identifying excess reagent and the limiting of the reaction :
8 H2S(g) + 4 O2(g) = S8(I) + 8 H2O(g)
8 x 34 g H2S --------> 256. 52 g S8
35.0 g ----------------> ??
35.0 x 256.52 / 8 x 34 =
8978.2 / 272 => 33.00 g of S8
H2S is the limiting reactant
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4 x 31.99 g O2 --------------- 256.52 g S8
40.0 g O2 --------------------- ??
40.0 x 256.52 / 4 x 31.99 =
10260.8 / 127.96 = 80.16 g of S8
O2 is the excess reagent is the excess <span>reagent
</span>
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H2S is the limiting reactant, one that is fully consumed, it is he who determines the mass of S8 produced
33.0 g ----------- 100%
?? g ------------- 95 %
95 x 33.00 / 100 => 31.35 g
hope this helps!
This is so that all measurements can be used without having to calculate from different units.