1.  The ratio of iron atoms to chromium atoms in a water sample from the treatment pond at ZGlobe is11to7. If there are208chromium atoms in a liter of the water, how many iron atoms are there in a liter? Round your answer to the nearest whole number if needed.

 2.  Hailey worked overtime at the lab to perform a chemical analysis on some sludge of unknown composition. She found it to be24.3% water by mass. If she completely dried a115g (original mass) of the sludge, how much water was removed in the drying process? Round your answer to the nearest hundredth.


3.  In a mixture of CaCO3 and C_{un}SO_{4}the ratio of C_{un}CO_{3}to C_{un}SO_{4}molecules is7to4. If there are20billion molecules of C_{un}SO_{4}, how many total molecules are in the mixture?

 4.  According to the instructions for a chemical procedure, Sean mixed salt, baking soda and water in a2:1:25ratio by mass. How many grams of water would be required to make a mixture that contained16grams of salt?


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 6.  For every five hundred thousand pounds of fertilizer manufactured at Bigearth, Inc., about440pounds are ruined by being accidentally left out in the rain. Last month,200pounds were ruined. Based on this information, estimate how many pounds of fertilizer were manufactured last month. Round your answer to the nearest whole number if needed.

