A student mixes 20% acid solution with a 40% acid solution to produce 20 liters of a 28 acid solution how many liters of a 20% acid solution. How many liters of the 20% acid solution was needed

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Mary is conducting an experiment on how pollution affects plant growth. how can she ensure that her data are reliable?

Inside a flashbulb, oxygen surrounds a thin coil of magnesium. when the flashbulb is set off, a chemical reaction takes place in which magnesium combines with oxygen to form magnesium oxide. which of the chemical equations matches the reaction above? a. mg + o2 mgo2 + energy b. 2mg + o mg2o + energy c. 2mg + o2 2mgo + energy d. mg + o mgo + energy