Assuming that air contains 78 percent N2, 21 percent O2, and 1.0 percent Ar. all by volume, how many molecules of each type of gas are present in 1.0 L of air at STP?
Chapter 10: Gases Wednesday, November 9, 2016 3:00 PM Unlike solids and liquids, gases; Expand to fill their containers (no fixed shape or volume) Highly compressible Extremelylow densities Expand when heated Have large distances between particles (atoms/molecules) Always form homogeneousmixtures Air Mixture- Nitrogen, oxygen, argon, carbon dioxide Substances that are gases at normal temperaturesand pressures are either monoatomic or small nonmetal molecules. The reason substances at normal temp/pressuresexist in the gas state is they lack the intermolecularforces which keep other substances as liquids or solids. Reactions which generate gaseous product(s)- • Single replacement • Combustion • Decomposition Pressure Pressure = force/area P = F/A Units: