concept 2 Flashcards
what is an acid?
a compound that dissolves in water to form a pH lower than 7
what is acute toxicity?
reaction to a harmful substance after a single exposure
what is chronic toxicity?
reaction after many repeated exposures
what is a base?
a compound that dissolves in water to form a pH higher than 7
what are heavy metals?
metals that have a density of five or higher. are one type of substance monitored to determine water quality
what is an indicator?
living things in the environment
what are invertebrates?
animals without any backbones
what is LD50?
the amount of a substance that can kill 50% of a group of organisms (mainly test animals receiving the same amount of that substance at the same time)
what is monitoring?
keeping track of something for a specific purpose
what does “neutral” mean?
a substance that is neither an acid or a base
what is neutralization?
a reaction between an acid and a base that produces water and a solid compound called salt
what is “pH”?
power of hydrogen. the number of hydrogen ions in a solution
what does “parts per million” mean?
measuring how something has one part of solute for a million parts of a solution
what does “toxic” mean?
something is poisonous or polluted
what is toxicity?
how poisonous a substance is
what provincial and federal governments classify water quality as? (5)
human drinking water, livestock drinking water, recreation, irrigation, protection of aquatic life
what was DDT?
an insecticide that was used to kill off harmful organisms, especially mosquitos
why is dissolved oxygen important?
it’s essential for the health of the aquatic life
what does the level of dissolved oxygen in an environment depend on? (4)
temperature, turbulence, the amount of photosynthesis, the number of organisms using up the oxygen
what is “spring acid shock”?
when acid builds up in snow and ice in the winter, then, in the spring, the snow and ice will melt into aquatic systems
what happens when phosphorus and nitrogen content get into aquatic systems?
they die and become food for bacteria > bacteria numbers increase > use of dissolved oxygen > when the dissolved oxygen content decreases, many fish/aquatic insects cannot survive
what happens when a blue litmus is placed into a substance?
it will turn red if the substance is acidic, and it will stay blue if the substance is basic
what happens when a red litmus is placed into a substance?
it will stay red if the substance is acidic, and it will turn blue if the substance is basic
