Ch. 11 - Ch. 11 - StoichiometryStoichiometry

Mole to Mole ConversionsMole to Mole Conversions

The equation for a turkey The equation for a turkey sandwich might look like:sandwich might look like:

2 turkey + 1 cheese 2 turkey + 1 cheese + 2 bread+ 2 bread

1 turkey sandwich1 turkey sandwich

The coefficents in the balanced The coefficents in the balanced chemical equation show chemical equation show RELATIVE numbers of moles of RELATIVE numbers of moles of each substanceeach substance

In other words, it is telling you In other words, it is telling you the RATIO of molesthe RATIO of moles

You can have more or less than You can have more or less than the values given but they are the values given but they are still in the same proportionstill in the same proportion

We need these MOLE We need these MOLE RATIOS!RATIOS!

If you know the actual If you know the actual number of moles of one of the number of moles of one of the substances in the balanced substances in the balanced equation, you can determine equation, you can determine the number of moles of the the number of moles of the others substances too…using others substances too…using the MOLE RATIO.the MOLE RATIO.

Practice Problem #1:Practice Problem #1:NHNH44NONO33 N N22O + 2HO + 2H22OO

a) You have 4.2 moles of NHa) You have 4.2 moles of NH44NONO33 reacting, how many moles of Hreacting, how many moles of H22O O are produced?are produced?

4.2 mol NH4.2 mol NH44NONO33 x ___________ = x ___________ =

b)b) How many moles of NHow many moles of N22O are O are produced?produced?

4.2 moles NH4.2 moles NH44NONO3 3 x ___________ = x ___________ =

Practice Problem #2:Practice Problem #2:2HCl + Zn 2HCl + Zn ZnCl ZnCl22 + H + H22

How many moles of HCl are needed to How many moles of HCl are needed to react with 2.3 moles of Zn?react with 2.3 moles of Zn?

2.3 mol Zn x ___________ =2.3 mol Zn x ___________ =

Practice Problem #3:Practice Problem #3:__ C__ C66HH1212OO66 + __ O + __ O22 __ CO __ CO22 + __ H + __ H22OO

If 3.20 mol of CIf 3.20 mol of C66HH1212OO66 react, how many moles react, how many moles of Oof O22 react? react?

CC66HH1212OO66 + + 66 O O22 66 CO CO22 + + 66 H H22OO

3.20 mol C3.20 mol C66HH1212OO66 x x 6 mol CO6 mol CO22 = 19.2 mol CO = 19.2 mol CO22

1 mol C1 mol C66HH1212OO66