Question

At 40.0°C, the pressure inside a nitrogen-filled tennis ball with a volume of 148

cm is 235 kPa. How many moles of nitrogen (N2) are in the tennis ball?
A 13.4 mol
B 4.22 * 102 mol
C 1.34 x 10-2 mol
OD 0.105 mol

Answer 1

the answer is

n = 0.01336 mol

Step-by-step explanation:

To determine the number of moles of a gas, we need to have an expression that relates the pressure, temperature and volume of the system. For simplification, we assume that this gas is ideal so we use the equation PV=nRT. We calculate as follows:

PV=nRT

n = PV / RT

n = 235000(1.48x10^-4) / (8.314)(40+273.15)

n = 0.01336 mol

Answer 2

Answer : The correct option is, (B)
`1.34* 10^2mol`

Explanation :

To calculate the moles of nitrogen gas we are using ideal gas equation:

`PV=nRT`

where,

P = pressure of nitrogen gas = 235 kPa = 2.319 atm

Conversion used : (1 atm = 101.325 kPa)

V = volume of nitrogen gas =
`148cm^3=148mL=0.148L`

Conversion used : (1 L= 1000 mL)

T = temperature of nitrogen gas =
`40.0^oC=273+40.0=313K`

R = gas constant = 0.0821 L.atm/mole.K

n = moles of nitrogen gas = ?

Now put all the given values in the ideal gas equation, we get:

`(2.319atm)* (0.148L)=n* (0.0821L.atm/mole.K)* (313K)`

`n=0.0134mol=1.34* 10^2mol`

Therefore, the number of moles of nitrogen gas are,
`1.34* 10^2mol`