Chemistry · Introduction to Fundamental Concepts of Chemistry
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30 grams of 2-propanol were mixed with excess acidified K2Cr2O7 and boiled under reflux for 20 minutes. The organic product was then collected by distillation. The yield of product was 75.0%. What is the mass of product produced?
- A
1.74g
- B
21.75g
- C
2.74g
- D
29 g
To calculate the mass of the product produced, you can use the yield percentage.
The yield percentage is calculated as follows:
Yield (%) = Actual Yield / Theoretical Yield × 100
In this case, the yield is given as 75.0%, and mass of 2-propanol is 30 grams.
The molecular formula of 2-propanol (isopropanol) is C3H8O.
Molar mass of C3H8O = (3 * 12.01 g/mol) + (8 * 1.01 g/mol) + (1 * 16.00 g/mol) = 60.03 g/mol
Theoretical Yield = (Mass of 2-propanol) × (Theoretical Yield / Molar Mass of 2-propanol)
Theoretical Yield = (30 g) × (1 mol / 60.03 g) = 0.4999 mol
Now, calculate the actual yield using the given yield percentage:
Yield (%) = (Actual Yield / Theoretical Yield) × 100
75.0% = (Actual Yield / 0.4999 mol) × 100
Actual Yield = (75.0% / 100) × 0.4999 mol = 0.3749 mol
Now, convert the actual yield from moles to grams using the molar mass of the product you expect to obtain.
Actual Yield (grams) = 0.3749 mol × 60.03 g/mol = 22.51 g
So, the mass of the product produced is approximately 22.51 grams, which is closest to option (b) 21.75g.
According to given data, this option is incorrect.
To calculate the mass of the product produced, you can use the yield percentage.
The yield percentage is calculated as follows:
Yield (%) = Actual Yield / Theoretical Yield × 100
In this case, the yield is given as 75.0%, and mass of 2-propanol is 30 grams.
The molecular formula of 2-propanol (isopropanol) is C3H8O.
Molar mass of C3H8O = (3 * 12.01 g/mol) + (8 * 1.01 g/mol) + (1 * 16.00 g/mol) = 60.03 g/mol
Theoretical Yield = (Mass of 2-propanol) × (Theoretical Yield / Molar Mass of 2-propanol)
Theoretical Yield = (30 g) × (1 mol / 60.03 g) = 0.4999 mol
Now, calculate the actual yield using the given yield percentage:
Yield (%) = (Actual Yield / Theoretical Yield) × 100
75.0% = (Actual Yield / 0.4999 mol) × 100
Actual Yield = (75.0% / 100) × 0.4999 mol = 0.3749 mol
Now, convert the actual yield from moles to grams using the molar mass of the product you expect to obtain.
Actual Yield (grams) = 0.3749 mol × 60.03 g/mol = 22.51 g
So, the mass of the product produced is approximately 22.51 grams, which is closest to option (b) 21.75g.
According to given data, this option is incorrect.
According to given data, this option is incorrect.
Tagged under Chemistry · Introduction to Fundamental Concepts of Chemistry · 2022