environmental chemistry Flashcards
(23 cards)
what is the independent variable
the independent variable is the variable we decide to change
what is the dependant variable ?
the variable in which we measure
what is the control variable?
the variable(s) we must keep the same (constant)
what is burning known as scientifically?
combustion
what are the products of complete combustion?
carbon dioxide and water
what are the products of incomplete combustion?
carbon monoxide and water or carbon and water
what is a “conservation of mass”?
when, in a chemical reaction, mass is neither gained nor lost
what are catalysts?
catalysts are substances that speed up the rate of a reaction without being used up itself
why do industries use catalysts?
to speed up the reaction and lower costs
what is acid rain?
a substance in which sulphur dioxide and nitrogen dioxide has been dissolved making it acidic
what does acid rain tend to react to?
rocks and buildings made of limestone
what is global warming?
global warming is the process in which the atmosphere is heating up over time
what are some examples of gases that contribute to global warming?
carbon dioxide, water vapour and methane
what are 2 effects of global warming?
severe weather changes and rising sea levels
what is the carbon cycle?
the carbon cycle is the process of many stages in which the element carbon moves between non-living materials and living creatures and back again
what are the five stages of LCA?
extraction, processing, manufacture, use and disposal
what are the precise measurements?
precise measurements are ones where there is little spread about the mean value
what are accurate measurements?
accurate measurements are close to the true value
what are valid experiments?
valid experiment answer the question being asked
what are 3 examples of fossil fuels?
coal, oil, and gas
what can decrease nitrogen dioxide in cars?
a catalytic converter
what can catalysts do?
catalysts lower the energy needed
“catalysts are specific”, what does this mean?
different catalysts work better for different reactions - ex. manganese oxide for zinc chloride
