32) In some water purification plants, solid matter is skimmed off the top of the water. This is separating a mixture by what method?
A)
chromatography
B)
evaporation
floatation
D)
sifting

If 34.2 grams of lithium react with excess water, how many liters of hydrogen gas can be produced at 299 kelvin and 1.21 atmospheres? 2 li (s) + 2 h2o (l) yields 2 lioh (aq) + h2 (g)

•what conclusions can you make about the relationship between the volume of a gas and its temperature? • what conclusions can you make about the relationship between the volume of a gas and its pressure? • what possible variables have you not accounted for? as you did the procedures, is it possible that the atmospheric pressure may have changed? if it did change over the course of your experiment, then how would your results have been affected?

All chemicals, even safe chemicals, such as sodium chloride( table salt), are toxic if exposure is high enough. (true or false)