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Question 13 of 323.0/ 3.0 PointsSolid Iron (III) reacts with oxygen gas to form iron (III) oxide, which is the compound we see when rust is present. Based on this information, which of the following is true?4Fe + 3O2---> 2Fe2O3A. 4 moles of iron will need 2 moles of oxygen gas to fully reactB. 12 moles of iron, if reacted completely, can produce 8 moles of iron (III) oxide.C. 9 moles of oxygen can produce 9 moles of Iron (III) oxideD. 6 moles of oxygen can react completely to produce 6 moles of iron (III) oxide.E. none of the aboveFeedback: Great! Topic discussed in section 7.3-7.5.Question 14 of 323.0/ 3.0 Points`I have a buddy who recycles electronics, and isolates metals from the connector pins electrical boards. He isolates gold, for example, and purifies it the best he can, then sells it along with his other scrap metal. This last go around he was able to isolate 3.00 g of Au with a process he claims results in a 80.0% yield. If he is correct, what was his theoretical yield? In other words, hegot 3.00 g, but what should he have been able to get?
Feedback: Topic discussed in Chapter 5.Question 15 of 323.0/ 3.0 Points`Let's just consider the concept of stoichiometry without any confusing chemicals. Here is a generic equation: 2Q + 3R → 3S + 4T. If you mix 5 units of Q and 7 units of R, what would be the limiting reactant?Feedback: Great! Topic discussed in section 7.3-7.5.Question 16 of 32
3.0/ 3.0 Points`If you run a particular reaction, and in theory it was supposed to yield 50.0 grams of product, and the percent yield is 75%, how many grams did you actually end up with?Feedback: Topic discussed in Chapter 5.Question 17 of 323.0/ 3.0 PointsTo determine the limiting reactant in a chemical reaction, you need to know all of the following EXCEPT:A. the molar mass of each reactant present.B. the coefficient of each reactant in a balanced equation.C. the mass of each reactant present.
D. the mass of each product formed.Feedback: Great! Topic discussed in section 7.3-7.5.Question 18 of 323.0/ 3.0 PointsIf you ever watch a shuttle launch, you will see what looks like a crazy amount of smoke at the take off. But if you get up closer to the launch pad afterwards, you will see a bunch of ice! The reason is because hydrogen gas is the fuel, and it is being combusted with oxygen gas to form water: 2H2 + O2 → 2H2O. We will learn later why ice forms here even though it is so warm. But for now, what would be the total mass in grams of water (ice) if you completely combusted 150 kilograms of hydrogen gas? NOTE: All numbers located immediately after elemental symbols should be considered subscripts.Feedback: Great! Topic discussed in section 7.3-7.5.