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C1 Air quality

Twenty First Century Science

QuestionAnswerQuestionAnswerQuestion Answer
real difference you can be sure that the difference between two mean values is real if their ranges do not overlap molecule two or more atoms bonded together nitogen dioxide a gas which causes acid rain and makes breathing problems worse
best estimate the mean of a set of data catalyst speeds up a chemical reaction without being used up itself carbon dioxide a gas produces when fossil fuels are burned
accuracy how close a measurement is to the true value element a substance made from just one type of atom sulphur dioxide a gas which causes acid rain
mean value the average value combustion a chemical reaction with oxygen (burning) methane a gas produced by cows and rice fields which causes the greenhouse effect
range difference between the highest and lowest value in a set of measurements reactants chemical which react together emissions a polluting gas given out from a chemical reaction
outlier an odd measurement, very different from the rest, taht you suspect is wrong products new chemicals formed atthe end of a chemical reaction primary pollutant a harmful chemical that human activity adds directly to the atmosphere
hydrocarbons a chemical made from carbon and hydrogen atoms particulates microscopic soot particles atom smallest particle of a substance
Created by: j.punter