density of 20% by mass C2H6O2 solution in water is 1.03 g/mL. find the molarity of the solution.
62.07 is the molar mass, not the moles.
moles = 20.0g/molar mass = ??
100 mL/1.03 g/mL is 97.09 mL which is 0.09709 L.
20% by mass means 20 g C2H6O2 in 100 g soln.
moles C2H6O2 = 20/molar mass.
100 g soln. Use density to convert to L, then
M = moles/L
can i know ur answer bcus i got diff. from the actual ans,3.32M but i get 63.93 M.
if im wrong could you show me the conversion value to L (0.9709L) and the moles (62.07 mol).(is my calculation)
thanks...
Well, well, well, we have a chemistry question! Let's get this party started!
To find the molarity of the solution, we need to know the molar mass of C2H6O2 (which is also known as ethylene glycol). The molar mass of C2H6O2 = (2 * 12.01 g/mol) + (6 * 1.01 g/mol) + (2 * 16.00 g/mol) = 62.07 g/mol.
Now, let's assume we have 100 mL of the solution. Since the density is 1.03 g/mL, the mass of the solution would be (1.03 g/mL) * (100 mL) = 103 g.
In a 20% by mass solution, 20 g of ethylene glycol is dissolved in 100 g of water. Therefore, the mass of ethylene glycol in the solution is 0.20 * 103 g = 20.6 g.
To find the number of moles of ethylene glycol, we divide the mass by the molar mass: moles = mass / molar mass = 20.6 g / 62.07 g/mol = 0.332 mol.
Finally, we divide the moles by the volume in liters (which is 100 mL / 1000 mL/L = 0.1 L) to find the molarity: Molarity = moles / volume = 0.332 mol / 0.1 L = 3.32 M.
So, the molarity of the 20% C2H6O2 solution in water is 3.32 M. Voila!
To find the molarity of a solution, you need to know the mass of the solute (in this case, C2H6O2) and the volume of the solution.
Given:
Density of the solution = 1.03 g/mL
Let's assume we have 100 mL of the solution, as it makes the calculations easier.
Step 1: Finding the mass of the solution
Since the density of the solution is 1.03 g/mL, and we have assumed 100 mL of solution, we can calculate the mass of the solution using the formula:
Mass = Density × Volume
Mass = 1.03 g/mL × 100 mL
Mass = 103 g
Step 2: Finding the mass of C2H6O2
The solution is 20% by mass C2H6O2, which means that 20% of the total mass is C2H6O2.
Mass of C2H6O2 = 20% of Mass of the solution
Mass of C2H6O2 = 20/100 × 103 g
Mass of C2H6O2 = 20.6 g
Step 3: Finding the molarity
Molarity is defined as moles of solute per liter of solution. To find the molarity, we need to know the number of moles of C2H6O2 and the volume of the solution.
First, we need to calculate the number of moles of C2H6O2 using its molar mass.
The molar mass of C2H6O2 (ethylene glycol) =
2 × (12.01 g/mol) + 6 × (1.01 g/mol) + 2 × (16.00 g/mol)
= 62.07 g/mol
Number of moles of C2H6O2 = Mass of C2H6O2 / Molar mass of C2H6O2
Number of moles of C2H6O2 = 20.6 g / 62.07 g/mol
Number of moles of C2H6O2 = 0.3316 mol
Now that we have the number of moles of C2H6O2 and the volume of the solution (100 mL or 0.1 L), we can calculate the molarity.
Molarity (M) = Number of moles of solute / Volume of solution in liters
Molarity (M) = 0.3316 mol / 0.1 L
Molarity (M) = 3.316 M
Therefore, the molarity of the 20% by mass C2H6O2 solution in water is 3.316 M.