Chem 103 Lab Exam 3 Questions & Answers 100% Accurate!

Oxygen, O2 - ANSWERis a colorless, odorless gas that supports combustion. A glowing splint will brighten or burst into flame when thrust into the conatiner. Hydrogen, H2 - ANSWERis a colorless, odorless gas that burns in air. It is less dense than air and can be captured in an inverted vessel. A confined mixture of this and air (in an inverted test tube) will ignite with a "pop" when exposed to a flame. By contrast, pure __ will burn quietly with a blue flame if it replaces natural gas in a laboratory burner. Sulfur Dioxide, SO2 - ANSWERis a colorless gas that forms when sulfur burns in air. This gas is toxic since it can combine with water to form an acidic solution called sulfurous acid, H2SO3 (aq). In small quantities, it is safely used as a preservative for dried fruit. It is in the atmosphere, formed in the combustion of coal and oil, is a principal cause of acid rain. Nitrogen Dioxide, NO2 - ANSWERis a red-brown gas with heavy, burning odor. It is toxic, causing edema of lung tissue. It and other oxides of nitrogen are significant air pollutants and can contribute to the formation of acid rain. Ammonia, NH3 - ANSWERis a colorless gas with a sharp, suffocating odor. It is toxic and will burn in air. It is very soluble in water, forming solutions that are weakly basic. In solution, it is called aqueous ammonia and sometimes ammonium hydroxide. Carbon dioxide, CO2 - ANSWERis an odorless, colorless gas that does not burn; nor can it support combustion. For that reason, it is used to extinguish fires. When dissolved in water, it forms a weakly acidic solution known as carbonic acid, H2CO3 (aq). If bubbled through a solution of barium hydroxide or calcium hydroxide, a white precipitate of the carbonate salt forms, BaCO3 or CaCO3. Carbonate and bicarbonate salts produce carbon dioxide when treated with acid. Properties - ANSWERare identifying characteristics of matter Physical Properties - ANSWERproperties that can be determined without changing the substance into another substance Chemical Properties - ANSWERproperties that can be determined from the chemical reactions a substance undergoes