Jack M. Barrack Hebrew Academy 2012 – 2013, Tri 1 Honors Chemistry Dr. Darin Katz Lab Experiment #1- Evidence for Chemical Change The objectives of this lab experiment are: To observe the types of evidence that indicate a chemical change has taken place To identify reactants and products in a chemical reaction To identify and record how heat is involved in chemical change General Instructions1. Please read the attached lab sheets so that you are familiar with the procedure(s) and what type of data you will collect. 2. Please answer the pre-lab questions on the next page after reading the lab. Your completed pre-lab questions are due at the beginning of your lab period. They will count towards your grade on this lab. 3. Important safety items for this lab: wear goggles, apron, and gloves at all times; use caution when handling hydrochloric acid and sodium hydroxide; do not touch the top of the hot plate when using it. Instructions for Writing your Lab Report1. This will NOT be a formal lab report. Instead, your lab report should contain the following: (a) Title (b) Objectives of the experiment (look above ) (c) Observations on pages 32 - 33 (d) Completed Data Table on page 32 (e) Answers to post-lab questions 2. Remember to paste each lab sheet on a separate page of your lab notebook and start your Table of Contents. 3. Your lab report is due on: Jack M. Barrack Hebrew Academy 2012 – 2013, Tri 1 Honors Chemistry Dr. Darin Katz Lab Experiment #1- Evidence for Chemical Change Pre-lab Questions Name Please answer the following questions after reading your lab sheets. These completed questions are due at the beginning of your lab period. 1. List all important safety precautions for this lab experiment. 2. What is a reactant in chemical change? When writing a chemical equation, where do we find the reactant(s)? 3. What is a product in chemical change? When writing a chemical equation, where do we find the product(s)? 4. List four indications that a chemical change has occurred in the lab. (You may use class notes) 5. Briefly describe the proper and safe method for doing the following in the lab: (a) heating a substance in a test tube (b) detecting an odor in a flask Answer the following post-lab questions in your lab notebook. Type the question first and then give the answer. Post-Lab Questions 1. What are some causes of chemical changes? (Note: This is not asking for indications but the causes of chemical change.) 2. In what two ways was heat involved in chemical changes you observed in this lab experiment? Cite specific instances from the experiment. 3. Identify all of the reactants and products from this experiment. 4. From your list in Question #3, which are elements and which are compounds? Explain how you can differentiate between an element and a compound. 5. There are four indications that a chemical change occurred in the lab. You should have observed all four during this experiment. Cite specific instances from the experiment for each of the four indications.