A)
Cyclopropane is a has that is used as a general anesthetic. cyclopropane is a gas the gas has a density of 1.50g/L at 50 Celsius and 0.948atm. What is the molecular weight?
B)
The empirical formula of cyclopropane is CH2. What is the molecular formula?
can you explain the solution for A step by step?
Thanks! :)
Cyclopropane is a has that is used as a general anesthetic. cyclopropane is a gas the gas has a density of 1.50g/L at 50 Celsius and 0.948atm. What is the molecular weight?
B)
The empirical formula of cyclopropane is CH2. What is the molecular formula?
can you explain the solution for A step by step?
Thanks! :)
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You have to use the ideal gas law, which is PV=nRT. n is the number of moles in the compound, R is the constant 0.082058 atm*L/(K*mol). The temperature is given, which must be converted to kelvin, which is 273.15+50=323.15K. P is of course .948atm. Volume you assume to be 1L, and therefore mass is assumed to be 1.50 grams. The equation you must solve for is then:
n=(0.948*1)/(.082058*323.15)
n therefore equals .0357506mol.
Remember, the units for molecular weight are g/mol, so you must take the assumed number of grams of 1.50g and divide it by the number of moles, which is .0357506. 1.50/.0357506 is 41.957amu.
The molecular weight is 41.957amu, double check my calculations though.
For step B, finding the molecular formula is easy
first find the molecular weight of the empirical formula, which is 14.02658.
You divide the molecular weight from step one by the empirical formula weight to find the multiplier.
41.957/14.02658 is 2.99, which can be rounded to 3.
Multiply the number of each element in the empirical formula by 3 to find the molecular formula.
The molecular formula is therefore C3H6.
I know this is correct, because I know some organic chem, and I know that propane is a 3 carbon molecule, and the cyclo prefix means that each carbon is single bonded to each other in a triangle, and each carbon has two hydrogens bonded to it.
I hope this helped!
n=(0.948*1)/(.082058*323.15)
n therefore equals .0357506mol.
Remember, the units for molecular weight are g/mol, so you must take the assumed number of grams of 1.50g and divide it by the number of moles, which is .0357506. 1.50/.0357506 is 41.957amu.
The molecular weight is 41.957amu, double check my calculations though.
For step B, finding the molecular formula is easy
first find the molecular weight of the empirical formula, which is 14.02658.
You divide the molecular weight from step one by the empirical formula weight to find the multiplier.
41.957/14.02658 is 2.99, which can be rounded to 3.
Multiply the number of each element in the empirical formula by 3 to find the molecular formula.
The molecular formula is therefore C3H6.
I know this is correct, because I know some organic chem, and I know that propane is a 3 carbon molecule, and the cyclo prefix means that each carbon is single bonded to each other in a triangle, and each carbon has two hydrogens bonded to it.
I hope this helped!