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Teacherbot 27 Apr, 08:50:40

(a)

Let’s assume we have 100 g of the product.

60% of it is FeS, which means we have 60 g of FeS.

The remaining 40 g must be iron filings and sulphur that did not react.

From the ratio of 3:2, we know that for every 3 parts of iron filings, we need 2 parts of sulphur.

So, we can set up a proportion:

3 parts iron filings / 2 parts sulphur = x g iron filings / 40 - x g sulphur

Cross-multiplying:

3(40 - x) = 2x

120 - 3x = 2x

5x = 120

x = 24

So, we have 24 g of iron filings and 16 g of sulphur that did not react.

Therefore, the complete analysis of the product is:

FeS: 60 g

Fe (unreacted): 24 g

S (unreacted): 16 g

(b)

To determine the limiting reactant, we need to calculate the theoretical yield of FeS based on each reactant.

From the balanced chemical equation:

3Fe + 2S -> FeS3

Molar mass of Fe: 55.85 g/mol

Molar mass of S: 32.06 g/mol

Theoretical yield based on iron filings:

3 mol Fe x (1 mol FeS / 1 mol Fe) x (87.91 g FeS / 1 mol FeS) = 263.73 g FeS

Theoretical yield based on sulphur:

2 mol S x (1 mol FeS / 1 mol S) x (87.91 g FeS / 1 mol FeS) = 175.82 g FeS

Since we only obtained 60 g of FeS, we can see that iron filings are the limiting reactant.

To calculate the percentage of excess sulphur:

Amount of sulphur used: 2/5 x 100 g = 40 g

Amount of sulphur that did not react: 16 g

Excess sulphur: 16 g / 40 g x 100% = 40%

(c)

The degree of completion of the reaction can be calculated by comparing the amount of FeS obtained to the theoretical yield based on the limiting reactant.

The theoretical yield based on iron filings is 263.73 g FeS.

The actual yield is 60 g FeS.

Degree of completion = actual yield / theoretical yield x 100%

Degree of completion = 60 g / 263.73 g x 100% = 22.76%

Therefore, the reaction is only about 22.76% complete.

You 27 Apr, 09:05:28

Make this simpler to understand

Teacherbot 27 Apr, 09:05:28

We are trying to make ferrous sulphide (FeS) by heating iron filings and sulphur. We have 3 parts of iron filings and 2 parts of sulphur.

When we heat them, we get a product that contains 60% FeS. The rest is unreacted iron filings and sulphur.

To figure out how much of each reactant we used, we can set up a proportion. We find that we used 24 g of iron filings and 16 g of sulphur.

We can also see that iron filings are the limiting reactant, which means we didn’t have enough of it to react with all the sulphur.

We can calculate the percentage of excess sulphur, which is 40%.

Finally, we can calculate the degree of completion of the reaction, which is only 22.76%. This means that only a small amount of the reactants actually turned into FeS.