Question

Carbon monoxide gas is collected at 6.0°C in an evacuated flask with a measured volume of 10.0 L. When all the gas has been collected, the pressure in the flask is measured to be 0.210 atm Calculate the mass and number of moles of carbon monoxide gas that were collected. Round your answer to 3 significant digits. mass: 0 mole: - X 5 ?

Answer 1

Given

Pressure of CO gas = 0.210 atm

Volume of CO gas = 10.0 L

Temperature of CO gas = 6.0 ⁰ C = 279 K

No. of moles of CO gas = ?

Mass of CO gas = ?

We have relation , P V = n R T

where, P is a pressure of a gas, V is a volume of a gas, n is no. of moles of gas, R is a gas constant and T is temperature of gas.

$\therefore$ No. of moles of CO gas = P V / R T

No. of moles of CO gas = ( 0.210 atm $\times$ 10.0 L ) / ( 0.082057 L atm mol ^-1 K ^-1$\times$ 279 K )

No. of moles of CO gas = 0.091727 mol

ANSWER : No. of moles of CO gas = 0.0917 mol = 9.17 $\times$ 10 ^-02 mol

We know that, No. of moles = Mass / Molar mass

Molar mass of CO = 12.01 + 16.00 = 28.01 g /mol

Mass of CO gas = No. of moles of CO gas $\times$ Molar mass of CO

= 0.09173 mol $\times$ 28.01 g /mol

= 2.569 g

= 2.57 g

ANSWER : Mass of CO gas = 2.57 g