Question

Determine the number of moles of air present in 1.35 L at 750 torr and 17.0°C. Which equation should you use? COMPLETE What is the number of moles present? ​

Answer 1

0.0559 mol

Step-by-step explanation:

Step 1: Given and required data

• Volume of air (V): 1.35 L

• Pressure of air (P): 750 torr

• Temperature (T): 17.0 °C

• Ideal gas constant (R): 0.0821 atm.L/mol.K

Step 2: Convert "P" to atm

We will use the conversion factor 1 atm = 760 torr.

750 torr × 1 atm/760 torr = 0.987 atm

Step 3: Convert "T" to Kelvin

We will use the following expression.

K = °C + 273.15

K = 17.0 °C + 273.15 = 290.2 K

Step 4: Calculate the number of moles of air

If we assume air behaves as an ideal gas, we can calculate the moles (n) of air using the ideal gas equation.

P × V = n × R × T

n = P × V/R × T

n = 0.987 atm × 1.35 L/(0.0821 atm.L/mol.K) × 290.2 K = 0.0559 mol