Final answer:
To convert atmospheric pressure given in inches of mercury to atmospheres, multiply the inches by 25.4 to convert to mm, then divide by 760 mm Hg per atm. The result is the pressure in atm, which is approximately 0.875 atm for the given value of 26.18 inches.
Step-by-step explanation:
The student has asked how to convert atmospheric pressure from inches to atmospheres (atm). If we consider that the atmospheric pressure given is 26.18 inches of mercury (Hg), we'll need to convert this value to atm for use with the ideal gas law where the pressure is required in atm when using R = 0.0821 atm L/mol K. The conversion factor to remember is that 1 atm equals 760 mm Hg, which is equivalent to 29.92 inches Hg since there are 25.4 mm in an inch.
To convert 26.18 inches to atm, the calculation is as follows. First, we convert inches to mm by multiplying by 25.4, and then we use the conversion factor to convert to atm.
26.18 inches x 25.4 mm/inch = 664.972 mm Hg
Now, divide this value by 760 mm Hg per atm:
664.972 mm Hg / 760 mm Hg = 0.875 atm (approximately)
This conversion is essential to correctly apply the ideal gas law in physics and chemistry problems.