The air in a bicycle tire is bubbled through water and collected at 25 ∘C. If the total volume of gas collected is 5.65 L at a temperature of 25 ∘C and a pressure of 765 torr , how many moles of gas was in the bicycle tire?

0.232 moles from the gas, were in the bike tire

Explanation:

An easy problem to apply the Ideal Gases Law:

Pressure . volume = number of moles . R . T°(K)

T° must be in Kelvin → Absolute T° → 25°C + 273 = 298K

R = 0.082 L.atm/mol.K

Pressure must be in atm, because the units of R

765 Torr . 1 atm /760 Torr = 1.006 atm

Let's replace data: 1.006 atm . 5.65L = n . 0.082 L.atm/mol.K . 298K

n = (1.006 atm . 5.65L) / (L.atm/mol.K . 298K) → 0.232 moles

There were 0.233 moles of gas in the tire

Explanation:

Step 1: Data given

Temperature = 25.0 °C = 298 K

Volume = 5.65 L

Pressure = 765 torr = 765 /760 atm = 1.00657894737 atm

Step 2: Calculate moles of gas

p*V = n*R*T

⇒with p = the pressure of the gas = 1.00657894737 atm

⇒with V = 5.65 L

⇒with n = the mol of gas = TO BE DETERMINED

⇒with R = the gas constant = 0.08206 L*atm/mol*K

⇒with T = the temperature = 298 K

n = (p*V)/ (R*T)

n = (1.00657894737 * 5.65) / (0.08206*298)

n = 0.233 moles

There were 0.233 moles of gas in the tire