Victory for the ACT Student Text 15e

L ESSON 1 | D ATA R EPRESENTATION • 301

PASSAGE VI According to the kinetic molecular theory of gases, all gases consist of particles (atoms or molecules) in continuous, random motion. In an ideal gas, particles move freely without interacting with one another except for brief elastic collisions. Particles of a gas at a particular temperature will have a range of different speeds. The distribution of particle speeds, that is, the —„‡” ‘ˆ ’ƒ”–‹…Ž‡• ‘˜‹‰ ™‹–Š ƒ…‡”–ƒ‹ •’‡‡†ǡ ‹• ‰‹˜‡ „› –Š‡ ƒš™‡ŽŽǦ ‘Ž–œƒ †‹•–”‹„—–‹‘ curves. The most probable speed for the particles is represented by the peak of the curve. For a given distribution, the area under the curve corresponds to the total number of particles of a gas sample. ‘ ‹ŽŽ—•–”ƒ–‡ Š‘™ ƒ•• ƒˆˆ‡…–• ‘Ž‡…—Žƒ” •’‡‡†ǡ ‹‰—”‡ ͳ ‰‹˜‡• –Š‡ ƒš™‡ŽŽǦ ‘Ž–œƒ †‹•–”‹„—–‹‘• ˆ‘” –Š‡…‘‘ ‰ƒ•‡• Ž‹•–‡† ‹ –Š‡ –ƒ„Ž‡ ƒ– ƒ ϐ‹š‡† –‡’‡”ƒ–—”‡ ȋ͵ͲͲ ȌǤ ‘ ‹ŽŽ—•–”ƒ–‡ Š‘™ –‡’‡”ƒ–—”‡ ƒˆˆ‡…–• ‘Ž‡…—Žƒ” •’‡‡†ǡ ‹‰—”‡ ʹ ‰‹˜‡• –Š‡ ƒš™‡ŽŽǦ ‘Ž–œƒ distributions for nitrogen gas (N 2 ) at several temperatures. Table 1: Molar Mass of Common Gases (grams/mole) H 2 (hydrogen) 2.02 He (helium) 4.00 N 2 (nitrogen) 28.01 O 2 (oxygen) 32.00 Cl 2 (chlorine) 70.91 ” ȋ”›’–‘Ȍ 83.80

Figure 1