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A student measures the pressure, volume, and temperature of a gas in the laboratory and records the following data: P = 0.741 atm, V = 112 mL, T = 300 K Based on this information, what would be the volume of the gas at STP? Enter your answer to three significant figures in units of mL.

Respuesta :

Answer:

[tex]V_{2}  = 75.6 mL[/tex]

Explanation:

To solve this problem we will use the Ideal Gas Law, which forms the following formula

[tex]PV = nRT[/tex]

Where

[tex]P[/tex] = Pressure of Gas

[tex]V[/tex] = Volume of Gas

[tex]n[/tex] = Moles of Gas

[tex]R[/tex] = Constant = 0.0821 atm L/mol K

[tex]T[/tex] = Temperature of Gas

There are two states to consider

State 1 is given

[tex]P_{1}[/tex] = 0.741 atm

[tex]V_{1}[/tex] = 112 mL

[tex]n_{1}[/tex] = unknown

[tex]R_[/tex] = 0.0821 atm L/mol K

[tex]T_{1}[/tex] = 300K

State 2 is based on Standard Room Temperature Pressure (STP) which are fixed values

[tex]P_{stp}[/tex] = 1 atm

[tex]V_{2}[/tex] = unknown

[tex]n_{2}[/tex] = unknown

[tex]R_[/tex] = 0.0821 atm L/mol K

[tex]T_{2}[/tex] = 273.15K

Since this is the same mass of gas it can be reasoned that the moles of gas are the same. We rearrange the Gas Law Formula to the following

[tex]n = \frac{PV}{RT}[/tex]

We input the values and equate the formulas for both states by substituting the value of n

[tex]\frac{P_{1}V_{1}  }{RT_{1} } = \frac{P_{2}V_{2}  }{RT_{2} } \\ \frac{(0.741)(112)}{(0.0821)(300)} = \frac{(1)(V_{2}}{(0.0821)(273.15)}[/tex]

Answer

[tex]V_{2}  = 75.6mL[/tex]