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Answer the following question:

Calculate the mass of 45.0 L of F2 at 87.0° C and 750. mm Hg.

Use the Ideal Gas Law formula and here are values for R:

8.134 (L * kPa)/(mol * K)

0.0821 (atm * L)/(mol * K)

62.364 (L * mmHg)/(mol * K)

Include the following with your answer:

Which Gas Law constant did you use or which "R" value did you use? Why?
The numerical answer to the question.
An explanation of the correct number of significant figures you will use for the numerical answer.

Respuesta :

Answer: The mass of 45.0 L of [tex]F_{2}[/tex] at 87.0° C and 750 mm Hg is 56.605 g.

Explanation:

Given: Volume = 45.0 L

Temperature = [tex]87.0^{o}C[/tex] = (87.0 + 273) K = 360 K

Pressure = 750 mm Hg (1 mm Hg = 0.00131579 atm) = 0.98 atm

Formula used to calculate moles 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.

[tex]PV = nRT\\0.98 atm \times 45.0 L = n \times 0.0821 L atm/mol K \times 360 K\\n = \frac{0.98 atm \times 45.0 L}{0.0821 L atm/mol K \times 360 K}\\= \frac{44.1}{29.556} mol\\= 1.49 mol[/tex]

Moles is the mass of a substance divided by its molar mass. So, mass of [tex]F_{2}[/tex] (molar mass = 37.99 g/mol) is calculated as follows.

[tex]Moles = \frac{mass}{molar mass}\\1.49 mol = \frac{mass}{37.99 g/mol}\\mass = 56.605 g[/tex]

Thus, we can conclude that the mass of 45.0 L of [tex]F_{2}[/tex] at 87.0° C and 750 mm Hg is 56.605 g.