A volatile liquid was allowed to evorate in a 43.298g flask that has a total volume of 252mL.the temperature of the water bath was 100 celsius at the atmospheric pressure of 776 torr.the mask of the flask and condensed vapor was 44.173g.calculate the molar mass of the liquid.
252mL x 43.298/44.173=247mL
is this right?
no, no, no.
calculat the mass of the liquid, the final mass minus the mass of the flask.
calcuate the moles of liquid.
n=PV/RT t is in Kelvins
molar mass=massliquid/number moles.
is the answer for this one 7.22
Molar mass of 7.2? Not likely. What elements could it consist of?
would you please tell me the calculation....please
Try following the instructions.
From Bob Pursley.
calculat the mass of the liquid, the final mass minus the mass of the flask.
44.173-43.298 = ?? = mass liquid.
calcuate the moles of liquid.
n=PV/RT t is in Kelvins
substitute into n = PV/RT
molar mass=massliquid/number moles.
You have the mass liquid from the first part and the number of moles from the n = PV/RT. Just follow the process. If you still have problems, show your work to these calculations.
It seems like there was a misunderstanding in the calculation. Let me correct it for you.
To calculate the molar mass of the volatile liquid, you first need to find the amount in moles of the liquid that evaporated. Here's how you can do that:
1. Determine the mass of the liquid that evaporated. This can be found by subtracting the initial mass of the flask (43.298 g) from the final mass of the flask and condensed vapor (44.173 g):
Mass of evaporated liquid = final mass - initial mass
Mass of evaporated liquid = 44.173 g - 43.298 g = 0.875 g
2. Convert the mass of the evaporated liquid to moles. You can use the molar mass of the liquid to do this. However, since you don't know the molar mass yet, you'll need to use the ideal gas law to calculate the number of moles.
3. The ideal gas law is given by:
PV = nRT
Where:
P is the pressure of the system in atmospheres (convert 776 torr to atm by dividing it by 760)
V is the volume of the system in liters (convert 252 mL to L by dividing by 1000)
n is the number of moles of gas
R is the ideal gas constant (0.0821 L·atm/(mol·K))
T is the temperature in Kelvin (convert 100°C to Kelvin by adding 273.15)
4. Solve the ideal gas law equation for n:
n = (PV) / (RT)
Plug in the values:
P = 776 torr / 760 = 1.02 atm
V = 252 mL / 1000 = 0.252 L
R = 0.0821 L·atm/(mol·K)
T = 100°C + 273.15 = 373.15 K
n = (1.02 atm * 0.252 L) / (0.0821 L·atm/(mol·K) * 373.15 K)
5. Calculate the number of moles (n). This will give you the number of moles of the volatile liquid that evaporated.
Now that you have the number of moles (n) of the evaporated liquid and the mass (0.875 g), you can calculate the molar mass:
Molar mass (g/mol) = mass (g) / moles (mol)
Molar mass (g/mol) = 0.875 g / moles (mol)
Plug in the value of moles (mol) that you calculated in step 4 to find the molar mass.