At STP, 461 mL of a gas have a mass of 1.88 g. What is the molar mass of the gas?
PV = nRT and solve for n.
n = grams/molar mass and solve for molar mass. OR you can do it all at one time.
PV = nRT and n = grams/molar mass
PV = nRT/molar mass (let's call molar mass M), then
PVM = gRT and solve for M.
To find the molar mass of a gas, we can use the ideal gas law. The ideal gas law is expressed as:
PV = nRT
Where:
P = Pressure (in units of pressure, such as atmospheres, torr, or pascals)
V = Volume (in units of liters)
n = Number of moles
R = Ideal gas constant (0.0821 L∙atm/mol∙K)
T = Temperature (in units of Kelvin)
We are given that the volume of the gas is 461 mL, which we need to convert to liters. Since 1 liter is equal to 1000 mL, we can calculate the volume in liters:
V = 461 mL / 1000 mL/L
V = 0.461 L
We are also given the mass of the gas, which is 1.88 g. The number of moles can be calculated using the formula:
n = mass / molar mass
Rearranging the formula, we can solve for the molar mass:
molar mass = mass / moles
To calculate the number of moles, we need to convert the mass from grams to moles. The molar mass is the mass of one mole of a substance, which can be found on the periodic table.
Let's calculate the number of moles first:
n = 1.88 g / molar mass
Now we can rearrange the formula to solve for the molar mass:
molar mass = 1.88 g / n
To find the molar mass of the gas, we need the value of n (number of moles). Unfortunately, we don't have enough information to calculate the molar mass because we don't know the value of n. Additional information is needed to solve this problem.