Question 20 of 25 40 points if you ever watch a

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Question 20 of 25 4.0 Points `If 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 200.0 kilograms of hydrogen gas? NOTE: All numbers located immediately after elemental symbols should be considered subscripts. A.1784 kg B.1802 kg C.3604 kg D.200.0 kg E.not enough information Answer Key: A
Feedback: See section 8.6 Question 21 of 25 4.0 Points `You have to be careful about pouring drano down your pipes since it is mainly hydrochloric acid--you can't do it if they are made of aluminum because it will dissolve them! You can't acid clean your aluminum auto parts for the same reasons: 2 Al + 6 HCl → 2 AlCl3 + 3H2. If you were able to dissolve 10.0 mol of Al, how many many moles of hydrogen gas could you make? NOTE: All numbers located immediately after elemental symbols should be considered subscripts.
E.none of the above Answer Key: D Feedback: See section 8.6 Question 22 of 25 4.0 Points `Sodium and chlorine are very dangerous by themselves. However, when we combine them together in a chemical reaction, we eat it--it's table salt: 2Na + Cl2 → 2NaCl. If I have 5.00 mol of chlorine gas and excess sodium, how many moles if table salt could I theoretically make?
Feedback: See section 8.6 Question 23 of 25 4.0 Points `Chemistry is not always as simple as we are learning it, of course. Many times, reactions are linked, and the products of one reaction immediately become the reactants in another one. For example, 2 KClO3 → 3 O2 + 2 KCl, and then the oxygen produced goes on to make 2 Mg + O2 → 2 MgO. Suppose you begin with exactly 4 moles of potassium chlorate. If so, how much magnesium oxide can you produce? NOTE: All numbers located immediately after elemental symbols below should be considered subscripts. A.4 moles
Feedback: See section 8.6

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