Mass of flask, boiling chips, foil cap and unknown after cooling reaction 83.350g
2.Mass of flask, boiling chips,and foil cap. 82.657
3. water bath temperature C is 95.0 C
4. Barometric pressure inches of Hg 30.09
5. Accepted molar mass of unknown is 86.2g/moles
6. Volume of flask is 270 mls
Problem
1. Calculate mass of unknown.
2. Express water bath temperature in Kelvin
3. Express barometric pressure in standard atmospheric pressure
4. Express volume of flask in cm3
5. Calculate density of vaporized unknown.
Answers so far
1. 0.697 g
2. 368.15 K
3. 764.286
4. 270 cm3
5. How can I determine the vaporized unknown?
I believe 1 is not quite right. Probably just a typo but 83.350-82.657 = ??
2. ok.
3. 30.09 inches Hg x 25.4 mm/inch = 764.286 mm Hg which is ok. However, the question asks for atmospheres, not mm Hg so divide by 760.
4. ok
5. density. I am unsure exactly what you are doing.
P*molar mass = density*RT so you can calculate density BUT that doesn't use any of your data other than the molar mass. (It doesn't use the 0.693 g) so I don't think that is the approach to take.
However, you can calculate moles from
PV = nRT. From moles = grams/molar mass you can calculate experimental molar mass (which isn't 86.2), then
density = molar mass/22.4 g/mol which will give you the experimental density of the vapor.
A cubic piece of metal measures 6.50 on each edge. If the metal is nickel, whose density is 8.90 , what is the mass of the cube?
To determine the density of the vaporized unknown, you can use the Ideal Gas Law equation, which states:
PV = nRT
Where:
P = pressure
V = volume
n = number of moles
R = ideal gas constant
T = temperature
Since you have the accepted molar mass of the unknown and the mass of the unknown, you can calculate the number of moles using the formula:
n = mass / molar mass
Now, let's go step by step to calculate the density of the vaporized unknown:
1. Calculate the moles of the unknown:
Using the given mass of the unknown (0.697 g) and the accepted molar mass of the unknown (86.2 g/mol):
n = 0.697 g / 86.2 g/mol
2. Determine the volume of the vaporized unknown:
The volume of the vaporized unknown is the same as the volume of the flask, which is given as 270 mL.
3. Convert the volume of the flask to cm³:
Since 1 mL is equivalent to 1 cm³, the volume of the flask remains the same:
Volume = 270 cm³
4. Calculate the density of the vaporized unknown:
Density = mass / volume
Using the calculated mass of the unknown (0.697 g) and the volume of the flask (270 cm³):
Density = 0.697 g / 270 cm³
Therefore, the density of the vaporized unknown is the calculated value from the above equation.