Ch 6 Stoichiometry

Stoichiomerty - the study of amount use and the amount produce.

Basically, it's the measurement of element.

For example:
First)
 C10H8 + O2  >  CO2 + H2O  (First Step, Write the balance equation)
                            Into
1C10H8 + 12O2 > 10CO2 + 4H2O

Second)
Then we can determind the ratio of this reaction as  1:12:10:4 ( base on the first number in each substance)

Third)
"What you need"  over  "What you have".
Ex.1 How many moles of O2 are required to react with 0.350 moles C10H8

1: What you have: 0.350 moles C10H8, What you need: mol of O2

0.350 moles C10H8 x       (__12O2 mole___ )       >>>> 4.2 mole of O2

            what you have         (  1C10H8 mole   ) ratio

2: At STP, what volume of water would be produced from 21.2g of C10H8?

(Tips, once we know how to convert it back to mole, we 'll be able to convert it into gram, molecules, volume, molarity, that we 've already learned before.  "BETTER REVIEW")

21.2g C10H8  x           __Mole of C10H8_  >>>>  0.165625 mole of C10H8 (Don't round it as sigfig yet)
                                       (12x10+8)C10H8     

0.165625mole of C10H8 x  __4mole of Water__What you want >>  0.6625 moles of Water
                                            1 mole of C10H8     What you have

0.6625 moles of Water x   __22.4 Volume__  >> 14.84........   SIGFIG    > 14.8 at STP of H2O
                                            1mole of Water

As we 've seen that, it's pretty complicated, but not that hard, once we do it "STEP BY STEP" then it's easy to get marks

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