Answer:
9.68x10^21 molecules of nitrogen
Step-by-step explanation:
I will assume that r.t.p. is supposed to be STP, Standard Temperature and Pressure. rtp might refer to room temperature and pressue, but no value is given for room temperature, so let's assume standard temperature (0 degrees Celsius). Here is a marvelous, and useful, property of gasses at STP: One mole of gas at STP occupies 22.4 liters. Let's make that a conversion factor: (1 mole/22.4 liters).
We have the volume of gas at STP: 360 cm^3. Convert that into liters:
(360cm^3)*(1 ml/cm^3)*(1 liter/1000 ml) = 0.360 liters(L)
Now use the conversion factor from above to convert the volume of gas into moles of gas:
(0.360L)*(1 mole/22.4 liters) = 0.0161 moles of gas
By definition, 1 mole is 6.02x10^23 particles, or molecules of the gas.
Convert moles of the gas to molecules:
(0.0161 moles)*((6.02x10^23 molecules)/mole) = 9.68x10^21 molecules of nitrogen.