in an experiment, a 4.000grams sample of aluminum metal is added to a solution containing 5.000grams of dissolved iron chloride. the reaction results in the formation of aluminum chloride and metallic iron. when the reaction is complete, unreacted aluminum remains, and this unreacted aluminum is consumed by reaction with excess hydrochloric acid. the resulting solution was decanted off and the deposited Fe metal was washed several times with water. the wet Fe was transferred to a clean, dry evaporating dish, which weighted 30.7310grams. after carefully evaporating the water, the dish and the iron residue was found to weigh 32.9150grams.
A. calculate the experimental percentage of iron in the iron chloride
B. determine the empirical formula of the iron chloride
Second try. My first one was deleted.
32.9150g = mass dish + Fe
-30.7310g = mass empty dish
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+2.1840g = mass Fe
%Fe = (mass Fe/mass Fe sample) = 2.1840/5.000)*100 = ? = approx 43.68%
Note: I feel compelled to point out that this is a lousy procedure BECAUSE when the HCl is added to consume the unused Al metal, it will consume part of the solid Fe metal ALSO which means the results are low for the percentage of Fe.
b) Take a 100 g sample which give you
43.68 g Fe and
100 - 43.68 = 56.32g Cl
mols Fe = 43.68/55.85 = about 0.782
mols Cl = 56.32/35.45 = about 1.59
Divide both by the smaller of the two or
0.782/0.782 = 1.00 and
1.59/0.782 = 2.03 which I would round to 2 which makes the iron chloride empirical formula FeCl2.
what is the balanced chemical equation and how do you find the percent yield of iron in the experiment?
To calculate the experimental percentage of iron in the iron chloride, you need to first determine the amount of iron that was used in the reaction. This can be done by subtracting the weight of the iron residue from the weight of the evaporating dish before the water was evaporated.
The weight of the evaporating dish and the iron residue after the water was evaporated is 32.9150 grams.
The weight of the empty evaporating dish is 30.7310 grams.
To find the weight of the iron residue, subtract the weight of the empty dish from the weight of the dish and residue:
32.9150 grams - 30.7310 grams = 2.184 grams
Therefore, the weight of the iron residue is 2.184 grams.
Next, we need to calculate the experimental percentage of iron in the iron chloride by comparing the weight of the iron residue to the initial weight of the iron chloride.
The initial weight of the iron chloride is given as 5.000 grams.
To calculate the percentage, divide the weight of the iron residue by the initial weight of the iron chloride, and multiply by 100:
(2.184 grams / 5.000 grams) * 100 = 43.68%
Therefore, the experimental percentage of iron in the iron chloride is approximately 43.68%.
To determine the empirical formula of the iron chloride, you need to calculate the ratio of the moles of iron to the moles of chlorine in the compound.
First, calculate the moles of iron using the weight of the iron residue and the molar mass of iron:
Molar mass of iron (Fe) = 55.845 g/mol
Moles of iron = (2.184 grams / 55.845 g/mol) = 0.0391 moles
Next, calculate the moles of chlorine using the weight of the iron chloride, the weight of the iron residue, and the molar mass of chlorine:
Molar mass of chlorine (Cl) = 35.453 g/mol
Moles of chlorine = [(5.000 grams - 2.184 grams) / 35.453 g/mol] = 0.0761 moles
Finally, determine the ratio of moles by dividing the moles of iron and chlorine by the smallest number of moles:
Moles of iron / 0.0391 moles ≈ 1
Moles of chlorine / 0.0391 moles ≈ 2
The empirical formula of the iron chloride is FeCl₂.