Answer is A

How many of the following statements are true? A gas particle that is behaving ideally has no mass. The observed pressure of a real gas is higher than the expected ideal pressure. The gas particles of a theoretical ideal gas would not collide with each other. Carbon dioxide will behave more ideally than helium at the same conditions of pressure and temperature. At the same conditions of pressure and temperature, hydrogen molecules will collide with the walls of their container about twice as much as helium atoms. c) 3 d) 4 e) 5 b) 2 a) 1