Today's Agenda.m 1/3/11 Recall – ratios and fractions & Types of reactions Get your comp books out before the bell rings Check Stamps for unit 5 (During Recall and notes) Mole ratios notes and worksheet 10/25/2015

Quiz Quiz next Tuesday 1/11/11 10/25/2015

Recall Predict the following Chemical Reactions: 1.ZnCl 2 + Ag  2.Al(OH) 3 + H 2 C 2 O 4  3.Na + S  4.FeCl 2 + MgCO 3  5.AlCl 3  AgCl + Zn (Single Replacement) H 2 O + Al 2 (C 2 O 4 ) 3 (Neutralization) Na 2 S (Synthesis) FeCO 3 + MgCl 2 (Double R) Al + Cl 2 (Decomposition) 10/25/2015

Recall 2 Balance the following Chemical Reactions: 1.ZnCl 2 + Ag  AgCl + Zn 2.Al(OH) 3 + H 2 C 2 O 4  H 2 O + Al 2 (C 2 O 4 ) 3 3.Na + S  Na 2 S 4.FeCl 2 + MgCO 3  FeCO 3 + MgCl 2 5.AlCl 3  Al + Cl /25/2015 Balance the following Chemical Reactions: ZnCl 2 + 2Ag  2AgCl + Zn 2Al(OH) 3 + 3H 2 C 2 O 4  6H 2 O + Al 2 (C 2 O 4 ) 3 2Na + S  Na 2 S FeCl 2 + MgCO 3  FeCO 3 + MgCl 2 2AlCl 3  2Al + 3Cl 2

Intro to Stoichiometry 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. l 10/25/2015

Mole Ratios 10/25/2015 The moles of a substance involved in a chemical reaction are always in whole number proportions. EX: Given the balanced reaction: O 2 + 4HBr  2H 2 O + 2Br 2 For every one mole of O 2 there must be 4 of HBr reacting and there will be 2 moles of H 2 O and 2 of Br 2

Mole Ratios 10/25/2015 EX: Given the balanced reaction: O 2 + 4HBr  2H 2 O + 2Br 2 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 10/25/2015 EX: Given the balanced reaction: O 2 + 4HBr  2H 2 O + 2Br 2 1) If 2.00 moles of HBr react, determine the moles of O 2 reacting x mole ratio2.00 x = 0.50 mole of O 2

Mole Ratios 10/25/2015 EX: Given the balanced reaction: O 2 + 4HBr  2H 2 O + 2Br 2 2) If moles of H 2 O are produced, determine the moles of HBr reacting x mole ratio0.080 x =.16 mole of HBr

Homework Complete Mole Ratios Worksheet 5 pts. Show work, i.e. write out the ratios (fractions) no work = no points 10/25/2015