A 1.10g- sample contains only glucose and sucrose . When the sample is dissolved in water to a total solution volume of 25.0ML , the osmotic pressure of the solution is 3.78atm at 298K
a.What is the percent by mass of glucose in the sample?
b.What is the percent by mass of sucrose in the sample?
I answered this below.
To determine the percent by mass of glucose and sucrose in the sample, we can use the formula for osmotic pressure and the molar mass of each compound.
a. To find the percent by mass of glucose in the sample, we need to first calculate the moles of glucose and sucrose present in the solution.
1. Calculate the moles of glucose (C6H12O6):
- The molar mass of glucose is 180.16 g/mol.
- Given that the sample is 1.10 g and has a volume of 25.0 mL, we need to convert the volume to liters: 25.0 mL = 0.025 L.
- Calculate the moles of glucose using the formula: moles = mass (g) / molar mass (g/mol)
moles of glucose = 1.10 g / 180.16 g/mol
2. Calculate the moles of sucrose (C12H22O11):
- The molar mass of sucrose is 342.30 g/mol.
- Calculate the moles of sucrose using the same formula: moles = mass (g) / molar mass (g/mol)
moles of sucrose = (total moles of the sample) - (moles of glucose)
3. Calculate the percent by mass of glucose:
- The percent by mass is calculated using the formula: percent by mass = (mass of glucose / total mass of the sample) * 100
percent by mass of glucose = (mass of glucose / total mass of the sample) * 100
b. To find the percent by mass of sucrose in the sample, the calculation is similar to finding the percent by mass of glucose:
- The percent by mass of sucrose = (mass of sucrose / total mass of the sample) * 100
Therefore, to solve this problem, you need to substitute the values for each step into the relevant formulas to find the answers.