Question

What is the pressure of a 1.0 L flask containing 0.12 g of He at 25 c. (R=.0821 l atm/ mol k

Answer 1

7.33 atm

Explanation:

Given: V = 1 L, T = 25 + 273 = 298 K, P =? , n= ? m = 0.12 g

Number of moles of He (n) = mass of He/molar mass of He

                                               = 0.12/4

                                               = 0.03 moles

From Ideal gas equation,

PV=nRT

P = nRT/V

  = 0.03 × 0.821 × 298/1

  = 7.33 atm