THE EQUATION LAB!

PURPOSE:

To study different reaction types: Synthesis, decomposition, single

replacement, double replacement, and combustion

MATERIALS NEEDED:

evaporating dishtest tubesMnO2NaClO3

H2O2Pb(NO3)2K2SO4BaCl2

ZnCuMgCaCO3

splintsmethanoltongstest tube holders

graduated cylinders

BACKGROUND INFORMATION: NONE

PROCEDURE:

- Each of the following numbers corresponds to a station that is located in the laboratory. Go to the station number and follow the steps outlined. You do not need to do the stations in order - you may choose any station at any time. WRITE OUT THE CHEMICAL REACTIONS THAT TAKE PLACE AT EACH STATION AND WHAT TYPE OF REACTION IT IS and any observations you make there. All of the materials that you need will be located at the station.

STATION:

1. Light a Bunsen burner. Write out the chemical reaction – yes, there is one!

2. Use tongs to hold a piece of Mg in a Bunsen burner flame. DO NOT STARE DIRECTLY AT THE FLAME!!!

3. Use tongs to hold a piece of Cu in a Bunsen burner flame (Assume that a copper (II) compound forms).

4. Add a few pieces of Zn to about 10 mL of hydrochloric acid in a test tube. Light a wooden splint and hold it over the mouth of the test tube. (There are three reactions in this step!). Assume that wood is cellulose, C6H10O5. BE SURE TO WASH OUT THE TEST TUBE WELL - USE SOAP, WATER, AND A TEST TUBE BRUSH.

5. Mix 5.0 mL of aqueous potassium iodide with 5 drops of aqueous plumbous nitrate. (When you write the equation, use the solubility rules in your text to identify what the precipitate is). BE SURE TO WASH OUT THE TEST TUBE WELL - USE SOAP, WATER, AND A TEST TUBE BRUSH.

6. Add about .5 g of manganese dioxide (About the size of a BB) to about 10 mL of hydrogen peroxide IN A TEST TUBE. Mix this solution well. Test the gas that is produced with a glowing splint. A glowing splint does not have a flame, but is just that - glowing. MnO2 plays the role of the catalyst in this reaction and should be drawn above the arrow in the equation to show that it speeds the reaction along, but is not part of the actual reaction itself. (Do not write the splint reaction again!) BE SURE TO WASH OUT THE TEST TUBE WELL - USE SOAP, WATER, AND A TEST TUBE BRUSH.

7. Put 2 ml of methanol (CH3OH) in an evaporating dish. CAREFULLY light the liquid with a burning splint. (You don’t have to write the splint reaction again!). CAUTION - THE FLAME IS HOT AND DIFFICULT TO SEE - THE DISH WILL REMAIN HOT!

8. Put about 5.0 mL of aqueous potassium sulfate in a test tube. Add about 5 drops of barium chloride solution. (When you write the reaction, use the solubility rules in your text to determine what the precipitate is). BE SURE TO WASH OUT THE TEST TUBE WELL - USE SOAP, WATER, AND A TEST TUBE BRUSH.

9. Heat a test tube containing about 1 cm of calcium carbonate. USE A TEST TUBE CLAMP TO HOLD THE TEST TUBE! Test the gas produced with a burning splint. (You don’t have to write the splint reaction again!). BE SURE TO WASH OUT THE TEST TUBE WELL - USE SOAP, WATER, AND A TEST TUBE BRUSH.

10. CAREFULLY heat a test tube containing about .5 cm of sodium chlorate mixed with about .5 g of manganese dioxide. USE A TEST TUBE CLAMP TO HOLD THE TEST TUBE! POINT THE TEST TUBE AWAY FROM ALL OF THOSE AROUND YOU. Test the gas produced with a glowing splint. Manganese dioxide plays the role of the catalyst. (You don’t have to write the splint reaction again!). BE SURE TO WASH OUT THE TEST TUBE WELL - USE SOAP, WATER, AND A TEST TUBE BRUSH.

CONCLUSION:

  1. Write out molecular chemical reactions for all reactions that you witnessed in the course of this lab for each station. Total, there should be 12 reactions. Make sure you indicate physical states!
  2. Write net ionic equations for appropriate equations as well.
  3. In addition, record your observations in detail for each of the 10 stations that you visited. This conclusion should be broken up into 10 parts, one for the observations and reactions witnessed at each station.
  4. TELL ME WHAT TYPE OF REACTION EACH REACTION IS!