A sample of 7.55 g of He has a volume of 5,520 mL and a temperature of 123°C. What is its pressure in torr?

Question

A sample of 7.55 g of He has a volume of 5,520 mL and a temperature of 123°C. What is its pressure in torr?

in progress 0
Sapo 2 months 2021-08-22T18:22:28+00:00 1 Answers 3 views 0

Answers ( )

    0
    2021-08-22T18:24:26+00:00

    Answer: The pressure is 8451.2 torr.

    Explanation:

    Given: Mass of He = 7.55 g

    Volume = 5520 mL

    Convert mL into L as follows.

    1 mL = 0.001 L\\5520 mL = 5520 mL \times \frac{0.001 L}{1 mL}\\= 5.520 L

    Temperature = 123^{o}C = (123 + 273) K = 396 K

    Now, moles of He (molar mass = 4.00 g/mol) are as follows.

    No. of moles = \frac{mass}{molar mass}\\= \frac{7.55 g}{4 g/mol}\\= 1.8875 mol

    Formula used to calculate pressure is as follows.

    PV = nRT

    where,

    P = pressure

    V = volume

    n = no. of moles

    R = gas constant = 0.0821 L atm/mol K

    T = temperature

    Substitute the values into above formula as follows.

    PV = nRT\\P \times 5.520 L = 1.8875 mol \times 0.0821 L atm/mol K \times 396 K\\P = 11.12 atm

    Convert atm into torr as follows.

    1 atm = 760 torr

    11.12 atm = 11.12 atm \times \frac{760 torr}{1 atm}\\= 8451.2 torr

    Thus, we can conclude that the pressure is 8451.2 torr.

Leave an answer

Browse

Giải phương trình 1 ẩn: x + 2 - 2(x + 1) = -x . Hỏi x = ? ( )