Good Day! 11/5/2014

1. Good Day! 11/5/2014 • Starter: When balancing a combustion you need to have an even number in front of which product? • Today we are going to… • do a lab on the different types of reactions. • Tomorrow we will go through the analysis and have time to work on the Review. • Friday we will take the test.

2. Good Day 11/5/2014 • Starter: What is the equation for the reaction of AgNO3 and NaOH? • Today we will… • Finish up and turn in the combustion worksheet. • Go through the analysis for the Lab on the reactions. • Have time to work on the Review

3. Types of Chemical Reactions Lab • Combustion: You saw that the other day with the burning of methane, propane and ethanol. • C?H? + O2 CO2 + H2O • Composition: H2 hydrogen and O2 oxygen combined to make H2O in an wonderful ball of fire! • A + B  C is the general form for the composition of water it looks like2 H2 + O2 2 H2O

4. Now for the three remaining reactions: • The single replacement, the double replacement and the decomposition.Half of you will be doing the single replacement reactions first, and the other half will be doing the Double replacement reactions first. After you have finished you will switch stations.

5. Single Replacement • You are going to test the reactivity of two metals, Zinc and Copper with HCl. Both of which are found a penny (Zinc on the inside, and copper on the outside). • What do you do here? • Put the penny half into the test tube and then add enough acid to cover the penny.

6. Single Replacement • For Clean up:Send one person from your group over to the fume hood with your beaker and reaction, it will continue over night. PLEASE BE CAREFUL!While you are waiting for the other groups to finish up please answer the questions on your lab paper.

7. Double Replacement Procedure • First: Iron Chloride (FeCl3) with Sodium Carbonate (Na2CO3)Place four drops of each solution into the “chemplate”. • Next do the same thing with the Silver Nitrate (AgNO3) and Sodium Hydroxide (NaOH) • For Clean up: Send one person to the back sinks, dump your reaction out onto a paper towel and then throw it in the garbage, then rinse and dry your chemplate.

8. The Set up We will now need to move the tables into squares (two tables pushed together so that four people can work at one station)

9. Analysis: Single Replacement Results: • What did you see when you put the penny into the test tube with acid? • Bubbles = gas was formed, it smelled funny and….(for our next observation let’s test what happens when you put a burning splint into the beaker) • What do you think the gas was?Hydrogen gas the Zinc replaced the Hydrogen in the HCl but the Copper didn’t, this is because Hydrogen is more reactive than Copper but Zinc is more reactive than Hydrogen.

10. Analysis: Single Replacement • What does this tell you about the reaction? What do you think the equation looks like? Please write it out below. • Zn + HCl  H2 (g) + ZnCl2 • The Zinc is more reactive! • Cu + HCl  No Reaction • Hydrogen is more reactive and therefore Copper can not replace it) • These are both single replacements one element replacing another element. • A + BC  AC + B 2

11. Analysis: Double Replacement • First: Iron Chloride (FeCl3) with Sodium Carbonate (Na2CO3) • What did you see? • No Reaction • What would the reaction be if it did go?Iron (III) Chloride with Sodium Carbonate+3 -1 +1 -2 +3 -2 +1 -1 FeCl3 + Na2CO3 AB + CD  AD + CB 2 3 Fe2(CO3)3 + NaCl 6

12. Analysis: Double Replacement • Silver Nitrate (AgNO3) and Sodium Hydroxide (NaOH) • What did you see? • A brown color & a white solid was formed. • Write down what you think the Equation was below • AgNO3 + NaOH  • All the ions are are + or – one so the are all balanced. AgOH(s) +NaNO3 • solid

13. Finally for the Decomposition • Finally for the Decomposition we will now see Nitrogen Triodide decompose into Nitrogen gas and iodide gas. • Please write what you think the equation is below. • NI3 N2 + I2 • You now need to work on the review, finish it for tomorrow, it is your homework. 2 3