Step 1
The gas is considered to be ideal, so it will be applied:
P x V = n x R x T (1)
P = pressure
V = volume
n = number of moles
R = gas constant
T = absolute temperature
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Step 2
Information provided:
P = unknown
V = 45 L
n = 2.4 moles
R = 0.082 atm L/mol K
T = 97°C + 273 = 370 K
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Step 3
P is cleared from (1):
P = n x R x T/V = (2.4 moles x 0.082 atm L/mol K x 370 K)/45 L = 1.62 atm
Answer: P = 1.62 atm