A 250 mL flask initially contains argon at a pressure of 2.0 atm. Neon is added to the flask until the total pressure reaches 5.0 atm. What is the mole fraction of neon in the final mixture

The mole fraction of neon in the final mixture is 0.6

Explanation:

According to Dalton's law, the total pressure is the sum of individual pressures.

Given : =total pressure of gases = 5.0 atm

= partial pressure of argon = 2.0 atm

= partial pressure of Neon = ? atm    

According to Raoults law, the partial pressure of a gas is equal to its mole fraction mulitiplied by the total pressure.

= mole fraction of Neon

Thus mole fraction of neon in the final mixture is 0.6

it's c. elements are placed in rows based on how may valencies electrons have.