NAME DATE MATERIALS: (per group of 2 – 3 students) (per ...

1 Jeri A. Martin; T. L. Sims Middle School; Santa Rosa County; Pace, FL; Dec. 14, 2001 ENDOTHERMIC OR EXOTHERMIC The student knows that a transfer of thermal energy occurs in chemical reactions. NAME_____DATE_____ MATERIALS: (per group of 2 3 students) - 250 mL beaker (1) - Effervescent tablets (2 tablets = 1 package) - 100 mL water - Celsius thermometer (1) - paper towels (1 per student) - stop watch (1) (per student) - graph paper (1 piece) - colored pencils (1 blue and 1 red) - ruler (1) PROCEDURE: 1. Measure 100 mL of water into the beaker 2. Place the thermometer in the beaker with water. 3. Record the temperature every 30 seconds for 2 minutes. Record in the DATA CHART. 4. IMPORTANT: at the end of the 2 minutes have the effervescent package open and ready to put the tablets in the water.

2 (NOTE: Try not to touch the tablets with your hand. Moisture from your hand can cause the reaction to start early.) 5. Once you have your 4th temperature reading (2 minutes) place the 2 effervescent tablets in the water and continue the timing. Record the temperature of the tablets and water every 30 seconds for 2 minutes. Record in the DATA CHART. 6. At the end of the second set of 2 minutes clean up by removing the thermometer from the beaker, wash and dry off. Then, pour the effervescent solution in the sink, wash and dry off. 7. Graph the information from the DATA CHART. This will be a line graph. First 2 minutes will be colored red; last 2 minutes will be colored blue. The CONTROL = time, VARIABLE = temperature. Jeri A. Martin; T. L. Sims Middle School; Santa Rosa County; Pace, FL; Dec.

3 14, 2001 8. Answer the following question: What type of chemical reaction was this? Exothermic or Endothermic DATA CHART: WATER TIME TEMPERATURE 30 seconds ( minutes) 60 seconds ( minutes) 90 seconds ( minutes) 120 seconds ( minutes) WATER AND EFFERVESCENT TABLETS TIME TEMPERATURE 150 seconds ( minutes) 180 seconds ( minutes) 210 seconds ( minutes) 240 seconds ( minutes) Jeri A. Martin; T. L. Sims Middle School; Santa Rosa County; Pace, FL; Dec. 14, 2001 Endothermic or Exothermic K W L The student knows that a transfer of thermal energy occurs in chemical reactions.

4 K What do you KNOW? W What do you WANT to know? L What did you LEARN? 1. What happens to the temperature of a substance in an endothermic reaction? 2. What happens to the temperature of a substance in an exothermic reaction? 3. List some chemical reactions that are endothermic. 4. List some chemical reactions that are exothermic. Jeri A. Martin; T. L. Sims Middle School; Santa Rosa County; Pace, FL; Dec. 14, 2001 ENDOTHERMIC/EXOTHERMIC RUBRICS NAME_____DATE_____ The student uses appropriate procedures for safety in the classroom, home and community. The student knows that a transfer of thermal energy occurs in chemical reactions.

5 Category 4 3 2 1 Endothermic Identifies 4 reactions that are endothermic. Identifies 3 reactions that are endothermic. Identifies 2 reactions that are endothermic. Identifies 1 reaction that is endothermic. Exothermic Identifies 4 reactions that are exothermic. Identifies 3 reactions that are exothermic. Identifies 2 reactions that are exothermic. Identifies 1 reaction that is exothermic. Lab Safety All safety rules in the lab are followed. One or more safety rules not followed. Use of Lab Equipment Lab equipment used effectively with little or no direction from teacher. Lab equipment used effectively with some extra direction from teacher.

6 Lab equipment used effectively, but with guidance from teacher. Struggles with directions for using lab equipment. Lab Equipment Proper pieces of equipment used for all sections of the lab. One piece of equipment not used properly. Two pieces of equipment not used properly. Three or more pieces of equipment not used properly. Goal 3: # 8 The student completes all tasks and works/communicates effectively with other class members. The student completes most important tasks and works/communicates effectively with other class members. The student completes some of the important tasks and works/communicates effectively with other class members. The student shows minimal understanding of the tasks and is unable to work/communicate effectively with other class members.

7