SECOND SEMESTER: UNIT 1 STOICHIOMETRY Spring 2015

Agenda  Welcome  Seating Chart  Name Game  Personal/Student Info  Learning Targets  What do we already know?  Mole-Mole Ratios  Balancing Equations  Mass to Mass conversions??

Seating Chart  You need to arrange yourselves in alphabetical order ACROSS rows. You have 2 minutes.  GO!!

Review  Balance these equations:  __1_H 2 CO 3 +_1__Ca → __1_CaCO 3 + _1__H 2  If 3 moles of Ca are used how many moles of CaCO3?  _2_K 3 PO 4 +__3_Mg → _1__Mg 3 (PO 4 ) 2 +_6__K  If 2 moles of Mg are used how many moles of K are produced?  __1_CaC 2 +__2_H 2 O → __1_Ca(OH) 2 + _1__C 2 H 2  If 8 moles Ca(OH)2 are produced how many moles of CaC2 are needed?

Agenda 1/21/15  Turn in Syllabus Letters 1 st Hour: Lab Drawers  Stoich Notes  All types of conversions  Practice Mass-Mass conversions  HW: Complete Mass-Mass Assignment

Agenda 1/22/15  Turn in Syllabus Letters  Stoich Notes HW Check  Use HW/Notes and Flowchart  Notes on % Yield  Chalk Lab  HW: Complete analysis for Chalk Lab

Percent Yeild  It tells us how good our experiment was.  Experimental ValueX 100  Stoich Value  This tells us how far from the actual value we are.

Agenda 1/23/15  Complete Chalk Lab  Must complete Analysis 1 before finishing lab  Checked by Mr. Gustin  Review Unit 6 for Quiz Monday  HW: Unit 6 Review Quiz Monday  Chalk Lab due Monday

Agenda 1/26/15  Turn in Chalk Lab  Tomorrow for Late Credit  Unit 6 Review Quiz  Use your Stoich Flowchart  Complete Mass-Mass Worksheet (Stoich Practice)  You will need to do this for tomorrow’s activities  HW: Complete Mass-Mass

Agenda 1/27/15  Turn in Chalk Lab  Late Credit  Review Mass-Mass Hw  HW Quiz  Limiting Reactants  S’mores Lab  HW: Write up S’mores Lab

S’mores Safety  You MUST place a paper napkin down at your station.  No food touches these tables!!  You must use a weighing dish for your food items  No food touches the balances  Tip: Keep the marshmallow away from the flame it will burn!!!

Agenda 1/28/15  Discuss S’mores Lab  Factor Label  Limiting Reactant  Turn in Lab  Limiting Reactant Notes  Practice Problems with LR  HW: #1-5 on Limiting Reactants Worksheet

Limiting Reactant  S’mores Lab  When you run out of marshmallows, you can’t make s’mores.  Chemistry  When a reaction runs out of one reactant the reaction stops.  The reactant that runs out first is called…  THE LIMITING REACTANT

Practice Problem  2 Na + 1 Cl 2 → 2 NaCl  If there are 6 moles Na and 5 moles Cl 2  LIMITING REACTANT ________________  MOLES NaCl ________________

Practice Problem  2 Na + 1 Cl 2 → 2 NaCl  23.0 g Na and 71.0 g Cl 2  LIMITING REACTANTS_________________  MOLES NaCl_________________

Agenda 1/29/15  Discuss Limiting Reactant HW  What do I need to compare?  Intro Problem  Limiting Reactant Lab  Groups of 4…not 2  HW: Complete the Lab Write-Up

LR Check  Take out a half sheet of paper  NaHCO 3 + HC 2 H 3 O 2 → NaC 2 H 3 O 2 + H 2 O + CO 2 If I am given 1.5g of Sodium Bicarbonate and.88g of Acetic Acid, which reactant is my limiting reactant? (Hint: you may use any product to compare to).

LR Lab Safety  In this lab you will be working in groups of 4..not 2.  You will need goggles since we are using a weak acid.  When mixing the powder with the acid you must make sure the balloons are held firmly around the test tube top so they do not pop off and ruin your data.  When the data has been taken, make sure to throw away your balloons and clean your test tubes thoroughly.

Post Lab Calculation Hint  Here is your chemical equation.  Is it balanced??  NaHCO 3 + HC 2 H 3 O 2 → NaC 2 H 3 O 2 + H 2 O + CO 2

Agenda 1/30/15  Turn in Balloon Lab  Other types of Stoich Problems  Volume of gas  Number of molecules reacting  HW: #1-7 stoich packet

More Stoich  There are two more types of problems that we have not covered.  Take out your stoich flowcharts!!

Volume problems _____ C 6 H 14 + _____ O 2 → _____ CO 2 + _____ H 2 O  How many liters of oxygen are needed to burn 3.50g of C 6 H 14 ? Assume reaction is at STP.  How many liters of gas are in one mole at STP?

Volume problems 2 C 6 H O 2 → 12 CO H 2 O  How many liters of oxygen are produced by burning 3.50g of C 6 H 14 ? Assume reaction is at STP. Answer:8.66 L of oxygen  How many liters of gas are in one mole at STP? 22.4 L of gas at STP = 1 mole

Molecule problems 2 C 6 H O 2 → 12 CO H 2 O  How many molecules of carbon dioxide are produced by burning 3.62L of oxygen ? Assume reaction is at STP.  How many molecules are in a mole?

Molecule problems 2 C 6 H O 2 → 12 CO H 2 O  How many molecules of carbon dioxide are produced by burning 3.62L of oxygen ? Assume reaction is at STP. 6.14x10 22 molecules carbon dioxide  How many molecules are in a mole? 6.022x10 23 molecules = 1 mole

Agenda 2/4/15  Check Stoich Review  Hand back everything  Review Balloon Lab  Practice More Stoich Problems  Extra Time: Work on cheat sheet for Test Tomorrow

__ Cu + __ AgNO 3  __ Cu(NO 3 ) 2 + __ Ag  Balance this equation, you will need it in the next problem. 1, 2, 1, 2

1 Cu + 2 AgNO 3  1 Cu(NO 3 ) Ag  How many grams of silver would be produced from 3.50 grams of Cu? grams Silver

Zn + 2 HCl  ZnCl 2 + H 2  How many liters of H 2 gas will be produced when 50.0 grams of Zn is combined with 0.9 mol of HCl? LR = HCl L of Hydrogen Gas

___ Al + ___ HCl  ___ AlCl 3 + ___ H 2  Balance this equation, you will use it in the next problem. 2, 6, 2, 3

2 Al + 6 HCl  2 AlCl H 2  How many grams of Aluminum are needed to react with 171 grams of HCl? 42.2 grams of Al

___ C 4 H 10 + ___ O 2  ___CO 2 + __ H 2 O  Balance this equation, you will need it for the next problem. 2, 13, 8, 10

2 C 4 H O 2  8 CO H 2 O  What is the percent yield of water if you react 2.60 L of oxygen and only moles of water are actually formed? TY = moles Oxygen 82%

1 Cu + 2 AgNO 3  1 Cu(NO 3 ) Ag  How many grams of silver nitrate would be used to produce 15.0 grams of copper (II) nitrate? grams Silver nitrate

Agenda 2/5/15  Collect Stoich Review  Last Minute Questions??  You will need:  Cheat Sheet  Stoich Flowchart  Calculator I will give you all Periodic Tables  HW: None, next up Gases!!

Zn + 2 HCl  ZnCl 2 + H 2  How much excess reactant will be left over when 50.0 grams of Zn is combined with 0.9 mol of HCl? Excess Zn = 20.7g

Agenda 2/6/15  Deflategate Debate  Research articles and figure out where you stand on the topic  HW: None, have a great weekend

Gases Intro  What are gases?  What do you know about gases?  How do you think gases relate to chemistry?  Etc…

Deflategate  The New England Patriots were accused of deflating their footballs under NFL regulations during the AFC Championship game (the game before the Super Bowl). A deflated football is easier to grasp and throw especially on a cold day.  There are two sides to every story, it is your job to read and determine if you think the Patriots did deflate the footballs, or maybe it was the cold weather that had the effect on the balls.