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1. A small factory refines copper ore to produce copper. The factory can produce 95.7 metric tons of pure copper from the ore per day. If 27 boxcars filled with ore arrive, how long will it take to refine the ore to produce the copper? (Express your answer in days and hours):
  1 boxcar contains 14 metric tons of ore
  The ore contains 72.35% copper by mass;
  Hours:
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  days:
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2. Compound A has a solublility of 22 grams/100 grams water at 27^oC and 45 grams/100 grams water at 75^oC.
  1. How much water (in grams) is needed to dissolve 48 grams of the compound at 27^oC?
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  2. A 35 gram sample of the compound is added to 85 grams of water at 75^oC The solution is then cooled to 27^oC. How many grams of A will crystallize out at 27^oC?
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3. Iron can be produced by reacting iron (III) oxide with carbon monoxide at high temperatures according to the following balanced equation: Fe₂O₃(s) + 3 CO(g) -> 2 Fe (s) + 3CO₂(g)
  1. How many grams of iron can be produced from 1.00x10³ grams of iron (III)oxide? (Assume an excess of carbon monoxide is available).
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  2. If 625 grams of carbon monoxide is available to react with 1.00x10³ grams of iron(III) oxide, how many grams of carbon dioxide are produced?
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    The question then asked for the name of the limiting reagent.
4. A compound is made up of Na, Br and O atoms. It contains (by mass) 15.2% Na and 53.2% Br. What is the simplest formula for the compound?
The following data was obtained in an experiment designed to determine the density of an unknown metal
Mass of falsk + stoper = 29.245 grams
Mass of clask+stopper+ethanol= 48.639 grams
Density of ethanol = 0.789 grams/m
Mass of flask + stopper + metal = 54.623 grtams
Mass of flask + stopper + metal + ethanol + 71.776 grams
Using the data above, calculate
1. The volume of the flask (in m)
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2. The mass of the metal
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3. The volume of the metal (in m)
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4. The density of the metal (in grams/m)
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BONUS
A flask filled with bromine has a mass of 103.54 grams. The same flask filled with methanol has a mass of 45.32 grams. The density of bromine is 3.12 grams/m while that of methanol is 0.791 grams/m. What is the mass of the flask?
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Query, are the (above) answers correct?