# How many moles are contained in 78.41 L of Ne at STP?

##### 1 Answer

Jun 12, 2014

In 78.41 liters of neon gas at STP, you have 3.498 moles of the gas.

Use the ideal gas law to calculate the value of moles.

The ideal gas law is PV=nRT

P is pressure which is 1 atmospheres for standard conditions.

V is volume which in this problem is given as 78.41 liters.

n is the mole value which we are trying to obtain.

R is the universal gas constant which is

0.0821 liters x atmospheres/moles x kelvin

T is the temperature in Kelvin which 273 K for standard conditions.

Rearrange the equation to solve for n

n = PV/RT

n = ( 1 atm) ( 78.41 L)/[(0.0821 L atm/mol K)(273)]

n= 3.498 moles of Neon gas