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loveia
Feb 11, 2009, 09:23 PM
Here are two examples of chemical recipes:

Na+ + Cl- -> NaCl
1 mole of H2SO4 + 2 mole NaOH produce 1 mole Na2SO4 + 2 mole H2O

Based on the recipes above:

1. If I have 1 mole of NaCl
a. How many moles of sodium do I have?
b. How many moles of Chloride do I have?
2. If I want to make 5 moles of Na2SO4:
a. How many moles of H2SO4 do I need?
b. How many moles of NaOH do I need?
3. How much Na2SO4 can I make if I have:
a. 1 mole of H2SO4 and 2 mole of NaOH
b. 10 mole of H2SO4 and 20 mole of NaOH
c. 0.1 mole of H2SO4 and 0.2 mole of NaOH
d. 1 mole of H2SO4 and 20 mole of NaOH
e. 0.42 mole of H2SO4 and 0.65 mole of NaOH
f. 5 grams of H2SO4 and 5 grams of NaOH

rwinterton
Feb 11, 2009, 09:30 PM
1. If I have 1 mole of NaCl
a. How many moles of sodium do I have?
b. How many moles of Chloride do I have?

You have 1 Na in the formula, so you must have 1 "mole" of Na.

2. If I want to make 5 moles of Na2SO4: 5 Na2SO4 = 10 Na + 5 SO4
a. How many moles of H2SO4 do I need? 5 (provides SO4)
b. How many moles of NaOH do I need? 10 (provides Na)

You have 2 Na in the formula, so there are 2 "moles" of Na for every "mole" of Na2SO4 that you have. SO4 is the anion, so it's best handled as a group. You have 1 SO4 in the formula so each mole of Na2SO4 contains 1 mole of SO4(-2)

3. How much Na2SO4 can I make if I have:
a. 1 mole of H2SO4 and 2 mole of NaOH (1 SO4 + 2 Na. How can you combine them to form Na2SO4?)
b. 10 mole of H2SO4 and 20 mole of NaOH (10 SO4, 20 Na -- same question)
c. 0.1 mole of H2SO4 and 0.2 mole of NaOH (ditto)
d. 1 mole of H2SO4 and 20 mole of NaOH (now, NaOH is in excess, so all of it won't react. You can figure out how much will).
e. 0.42 mole of H2SO4 and 0.65 mole of NaOH (you should be able to figure this out by now)
f. 5 grams of H2SO4 and 5 grams of NaOH (ditto)


By the way, you should have placed this in Chemistry

espy14
Feb 9, 2010, 03:37 PM
If 3.00 moles of copper metal are reacted how many moles of silver metal will be produced?

espy14
Feb 9, 2010, 03:38 PM
If 3.00 moles of copper metal are reacted how many moles of silver metal will be produced?