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Today's Agenda .m 1/3/11

Recall – ratios and fractions & Types of reactionsGet your comp books out before the bell rings

Check Stamps for unit 5 (During Recall and notes)

Mole ratios notes and worksheet

04/20/23

Quiz

Quiz next Tuesday 1/11/11

04/20/23

Recall

Predict the following Chemical Reactions:

1.ZnCl2 + Ag

2.Al(OH)3 + H2C2O4

3.Na + S

4.FeCl2 + MgCO3

5.AlCl3

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AgCl + Zn (Single Replacement)

H2O + Al2(C2O4)3 (Neutralization)

Na2S (Synthesis)

FeCO3 + MgCl2 (Double R)

Al + Cl2 (Decomposition)

04/20/23

Recall 2Balance the following Chemical Reactions:

1.ZnCl2 + Ag AgCl + Zn

2.Al(OH)3 + H2C2O4 H2O + Al2(C2O4)3

3.Na + S Na2S

4.FeCl2 + MgCO3 FeCO3 + MgCl2

5.AlCl3 Al + Cl2

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Balance the following Chemical Reactions:

ZnCl2 + 2Ag 2AgCl + Zn

2Al(OH)3 + 3H2C2O4 6H2O + Al2(C2O4)3

2Na + S Na2S

FeCl2 + MgCO3 FeCO3 + MgCl2

2AlCl3 2Al + 3Cl2

Intro to Stoichiometry

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The word Stoichiometry comes from the Greek word “stoicho” meaning element and “meter” meaning measure.

Stoichiometry is the branch of chemistry dealing with quantities of substances that react in or are produced in chemical reactions.

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04/20/23

Mole Ratios

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The moles of a substance involved in a chemical reaction are always in whole number proportions.

EX: Given the balanced reaction:O2 + 4HBr 2H2O + 2Br2

For every one mole of O2 there must be 4 of HBr reacting and there will be 2 moles of H2O and 2 of Br2

Mole Ratios

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EX: Given the balanced reaction:O2 + 4HBr 2H2O + 2Br2

Given the moles of one substance in a reaction, the moles of any substance can be determined by multiplying by the mole ratio.

The mole ratio is “Where you’re going, divided by where you’re coming from”.

Mole Ratios

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EX: Given the balanced reaction:O2 + 4HBr 2H2O + 2Br2

1) If 2.00 moles of HBr react, determine the moles of O2 reacting.

2.00 x mole ratio

€

Going_ to

Coming_ from2.00 x

€

1

42.00 x = 0.50 mole of O2

Mole Ratios

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EX: Given the balanced reaction:O2 + 4HBr 2H2O + 2Br2

2) If 0.080 moles of H2O are produced, determine the moles of HBr reacting.

0.080 x mole ratio

€

Going_ to

Coming_ from0.080 x

€

4

20.080 x = .16 mole of HBr

HomeworkComplete Mole Ratios Worksheet 5 pts.

• Show work, i.e. write out the ratios (fractions)

• no work = no points

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