Larisa pumps up a soccer ball until it has a gauge pressure of 61 kilopascals. the volume of the ball is 5.2 liters. the air temperature is 32°c, and the outside air is at standard pressure. how many moles of air are in the ball?

a.
0.13 mol
b.
0.33 mol
c.
1.2 mol
d.
3.2 mol

B.  0.33 mol

We are given;

Gauge pressure, P = 61 kPa (but 1 atm = 101.325 kPa)

                               = 0.602 atm

Volume, V = 5.2 liters

Temperature, T = 32°C, but K = °C + 273.15

thus, T = 305.15 K

We are required to determine the number of moles of air.

We are going to use the concept of ideal gas equation.

       We know atmospheric pressure is 101.325 kPa or 1 atm

Total ball pressure = 1 atm + 0.602 atm

                               = 1.602 atm

That is;

PV = nRT

n = PV ÷ RT

therefore;

n = (1.602 atm× 5.2 L) ÷ (0.082057 × 305.15 K)

  = 0.3326 moles

  = 0.33 moles

Therefore, there are 0.33 moles of air in the ball.

it can be observed without changing the identity of the object.

it depends on what substance you're talking about as well as many other factors. in quantum mechanics, the observation of particles affects the observers ability to measure certain properties. for example: you can know the velocity of a particle, but you can't know it's position; or you can know it's position, but not it's velocity. it's like trying to find out where a grain of sand is by throwing other grains of sand at it. once you find out where it is, it's been moved. it's also like trying to find an answer to the question of whether or not a tree falling in a forest makes a sound if nobody is there to hear it. paradoxically, the only way to find out is to be there and hear it.