Name: Date: Lab Partners: Types of Reactions Lab Purpose: The purpose of this laboratory activity is to discover the characteristics of different types of reactions. Introduction: A large variety of chemical reactions go on around us at all times. Classifying these reactions helps to make sense of them and enables us to predict the products. This activity provides an opportunity to learn and apply one classification scheme. There are other classification schemes that you will learn as you continue your study of chemistry. ——¤—— Pre-Lab Assignment 1. Prepare observation and data tables for each section of the lab. Include space to record observations before, during, and after the reaction. 2. What are the four main types of chemical reactions? Make a table like the one below, and fill in with information about each of them. Type of Reaction Description Generic Equation 3. What are the signs that a chemical reaction has occurred? 4. What elements and compounds is air composed of? 5. Which of those elements and compounds is always needed to turn a metal into a metal oxide? 1 6. A burning wooden splint (stick) will react differently if it is in the presence of different gases. Describe what happens when it is in the presence of: A. Oxygen (O2): B. Hydrogen (H2): C. Carbon Dioxide (CO2): ——¤—— Safety Information Safety Precautions: Read all safety precautions and procedures. If you are not comfortable with any or all safety precautions or steps in the procedure, discuss your concerns with the instructor prior to starting the lab. Wear safety goggles, aprons, and appropriate attire at all times. Skin contact with all chemicals and solutions should be avoided. Acid Spills: Skin Spills: Begin rinsing the affected area immediately. Continue rinsing for at least 15 minutes. Inform the teacher so additional care can be provided as needed. General Spills: Move away from the area and inform the teacher immediately to determine appropriate spill containment procedures. Take materials only as needed, and return them as soon as you are finished. Remember that glassware can be cleaned and reused, and some materials need to be shared by more than one group. Dispose of all chemicals and waste as directed. Clean up the lab station by washing all glassware with soap and water, wiping down lab benches with wet paper towels, and placing or returning all glassware in their designated locations. ——¤—— Experimental Procedures Materials: Chemicals: Equipment: steel wool, sodium bicarbonate, magnesium ribbon, copper (II) sulfate solution, hydrochloric acid (HCl), water, zinc, barium nitrate solution, sodium sulfate solution watch glass, metal tongs, test tube tongs, burner, test tubes, 10-mL graduated cylinder, wood splint, electronic balance Procedure: Part I - Demonstration 1. Record the mass of a watch glass and the mass of the watch glass plus a piece of steel wool. 2. Predict how the mass will change after the steel wool is burned in a flame. 3. Observe and record what happens while the steel wool is held in the hot part of a flame for 30 seconds. 4. Observe and record how the steel wool appears after it has been heated. 5. Record the final mass of the watch glass plus steel wool. Types of Reactions Lab 2 Part II - Demonstration 1. Record the mass of an empty test tube and the mass of the test tube plus sodium bicarbonate. 2. Predict how the mass of the sodium bicarbonate will change after the test tube is heated in a flame. 3. Observe what happens when the test tube is held in a flame for 10-15 seconds. Record any changes and observations. 4. Observe what happens when a glowing wood splint is inserted in the test tube. 5. Observe the test tube as it is heated for 10-15 seconds at a time for up to 2 more minutes. 6. Record the final mass of the test tube plus sodium bicarbonate. Part III 1. Set up and label four test tubes (A, B, C, D) and add approximately 15 drops of the following: A) Copper (II) Sulfate; B) Water; C) Hydrochloric Acid; D) Water 2. Obtain two strips of magnesium ribbon and two small pieces of zinc (use tweezers for the zinc). 3. Carefully add the following to each test tube: A) Magnesium Strip; B) Magnesium Strip; C) Piece of Zinc; D) Piece of Zinc 4. Record any immediate changes. 5. Allow the solutions to sit for approximately 5 minutes and record final observations. 6. Dispose of the materials and waste as directed. Part IV 1. 2. 3. 4. 5. Observe the barium nitrate solution and the sodium sulfate solution. Add 3 mL of barium nitrate solution into a clean test tube. Clean the lowly add 3 mL of sodium sulfate solution and observe any changes. Record any final observations. Dispose of the materials and waste as directed. Final Clean up 1. Dispose of the materials and waste as directed. 2. Wash all glassware thoroughly with soap. Make sure graduated cylinders and test tubes have been thoroughly cleaned. 3. Wash hands thoroughly before leaving the lab. Types of Reactions Lab 3 Post-Lab Analysis & Conclusion – DUE Next Lab Day (_______________) Answer all the questions below based on the data and observations during the experiment. Use full sentences, if an explanation is required. If calculations are required, show all work in a neat and organized manner. 1. Review the reactions below and identify if a reaction occurred. Provide evidence from your observations to support your decision. Chemical Reaction Evidence Reaction? 1 Heating Steel Wool in Air 2 Heating Sodium Bicarbonate 3 Magnesium + Copper (II) Sulfate 4 Magnesium + Water 5 Zinc + Hydrochloric Acid 6 Zinc + Water 7 Barium Nitrate + Sodium Sulfate 2. Calculate the change in mass of the steel wool in Part I. Show all work. 3. What would have caused the change in mass? Use your observations to support your answer. 4. Calculate the change in mass of the sodium bicarbonate in Part II. Show all work. 5. What would have caused the change in mass? Use your observations to support your answer. 6. The reaction(s) in Part I is called a synthesis reaction. Explain why this is an appropriate name. Types of Reactions Lab 4 7. The reaction(s) in Part II is called a decomposition reaction. Explain why this is an appropriate name. 8. The reaction(s) in Part III is called a single replacement reaction. Explain why this is an appropriate name. 9. The reaction(s) in Part IV is called a double replacement reaction. Explain why this is an appropriate name. 10. Is it possible to classify the type of chemical reaction from observations alone? Explain. (Hint: What other information could be helpful in determining the type of reaction?) 11. What other information is needed in order to classify a reaction? Conclusion – Write a typed conclusion for your experiment that includes: One paragraph summarizing the experiment and your observations (4-5 sentences) Types of Reactions Lab 5