General Stoichiometry - 5 questions, help with any/all would be great! =D?

Question

Note- please do now just solve these for the answers, but give a brief explanation as to how you got them, so I can refresh my memory on how to do this branch of Chemistry again. Thanks!!!

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1. Several brands of antacid tablets use aluminum hydroxide to neutralize excess acid.

Al(OH)3(s) + 3HCl(aq) --> AlCl3(aq) + 3H20(l)

What quanity of HCl, in grams, can a tablet with 0.750g of Al(OH)3 consume? What quantity of water is produced?

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2) If 10.0 g of carbon is combined with an exact, stoichiometric amount of oxygen, (26.6g) to produce carbon dioxide, what mass, in grams, of CO2 can be obtained? (That is, what is the theoretical yield of CO2)

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3) The equation for one of the reactions in the process of reducing iron ore to the metal is:

Fe2O3(s) + 3CO(g) --> 2Fe(s) + 3CO2(g)

a) what is the maximum mass or iron, in grams, that can be obtained from 454g (1.00 lb) of Iron (III) oxide?

b) What mass of CO is required to reduce the Iron (III) oxideo to Iron metal?

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4. Burning Coal and oil in a power plant produces pollutants such as sulfur dioxide, SO2. The Sulfur-containing compound can be removed from other waste gases, however, by the following reaction:

2SO2(g) +2CaCO3(s) +O2(g) --> 2CaSO4(s) +2CO2(g)

a)name compounds involved in the reaction

b)what mass of CaCO3 is required to remove 155g of SO2?

c)what mass of CaSO4 is formed when 155g SO2 is consumed completely?

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5. Your Body deals with excess nitrogen by excreting it in the form of Urea, NH2CONH2. The reaction producing it is the combination of Arginine (C6H14N4O2) with water to give urea and ornithine (C5H12N2O2).

C6H14N4O2 +H2O --> NH2CONH2 +C5H12N2O2

if you excrete 95 mg of urea, what quantity of arganine must have been used? what quantity of ornithine must have been produced?

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thanks so much if you are able to answer and explain any of these 5 questions, as I cannot seem to find the way to solve such problems in my notes. :-)

Answer 1

LOL.  this branch of chemistry.  hee hee hee.  ROFL

Which exactly would that branch be?  LOL.

The one that deals with chemicals?

These questions are basic.

You understand NOTHING about chemistry if you don't understand how to solve these. (not IF you can solve them but understand the issues)

Hint #1  You have to balance the atoms on each side of the reaction

Hint #2  The atoms are represented by either one Capital Letter or Two

Hint #3 H, C, N, O, Ca, S, Fe, Cl are symbols of atoms (and elements - but I don't want to confuse you with strange new concepts)

Hint #5 The number of each type of atom has to be the same on both sides of the reaction

Hint #6 Add up all of the atoms of each type on the left then on the right.  If they are the same, the reaction balances (ignoring electronic charge which also has to balance - but ignore that for now)

Hint #7  2NaC3  means two Na atoms and 2x3=6 C atoms

HInt # 8 NaC3  means one Na and 3 C atoms

Hint #9  There's a "magic" way to solve all of these but its a highly guarded secret.  I'll let you in on it but -hee hee - you have to promise never ever to tell any non chemist! (or at least anybody who is not interested) Promise?  Here it is:  The weight of atoms of each element average to a secret number that is the same the world over.  We call it the "atomic weight".  A mole of these atoms weigh the atomic weight in grams.  A mole of C weighs 12.011g and a mole of H weighs 1.00797g.  Note that a mole of H2 magically weighs twice as much as a mole of H !!!!!!!  Wow.  Now you promised to keep a lid on it, right?

So, wonder of wonders we can convert the number of atoms in an equation to the weights involved just by having a table giving us the "atimic weights".  If only such a thing existed.

Hint #10.  A mole is just the name of a big number of things.  could be anything.  A mole of sand grains, a mole of stars.  Actually the number is so big that its really only useful for really small things like atoms.  THese are names of quantities with specific values (numbers) of units: one, two, a dozen, a mole.  Same thing (but bigger)

Hint #11 So.  What is the weight of CH4?  12+4*1=16.  You'll have to understand that.

Hint #12 So if an equation is   C + 2H2  --> CH4  and I have 0.016 grams of CH4 (to keep it simple)  how much H did I need to start with?

Its just a puzzle with both numbers of pieces (atoms) and weights of pieces (atomic or molecular weights).  In this case, I check to make sure the equation is balanced (it is) and so I convert from weight of CH4 to number of CH4 moles   .016 / 16 = .001 moles

Since the balanced equation tells me that I have 4H (or 2H2) for each CH4  and I have 0.001 moles of CH4, I must have started with .004 moles of H (or .002 moles of H2).  Be sure not to make the beginners mistake of thinking you started with .004 moles of 4H !!!!!.  you'll have to figure out why on your own. Anyway if a mole of H weighs 1.008g then 0.004 moles weigh ???  Eazy.

Hint #13  After you become facile at converting between number of and weight of a chemical, you'll have it.  The basic concept is called "Atomic theory".

I enjoyed your question's viewpoint immensely.  Hope you're not too offended by the sarcasm.  Its intended to be in good fun.

In your notes.  Your actually supposed to LEARN something in class.  I doubt if you'll make much of yourself if the only thing you get out of your classes are notes.  My guess is somebody's done a better job than you of writing it down.  Good luck!

Answer 2

hmm..idk. LOL