Chemistry I Honors Accuracy & Precision Lab Prelab: 1. Define accuracy. 2. Define precision. 3. Create a dartboard that is precise but not accurate using 5 dots. Procedure: 1. Go to Explore Learning and open the “Measuring Volume” gizmo. Use the 250mL beaker and the 50mL graduated cylinder. 2. Pour 45.0mL of water into the 250ml-beaker. 3. Now pour the water from the 250ml-beaker into the graduated cylinder. 4. Record the amount of water in the graduated cylinder. Record to 1 decimal place. Use the magnifying glass to see meniscus clearly. 5. Pour the water into the sink. 6. Repeat 4 times. Data: Trial 1 2 3 Volume in graduated cylinder (mL) Calculations: 1. Average your 5 volumes together. Keep 1 decimal place in your answer. Be sure to include a unit. 2. If the correct volume was supposed to be 63.0mL, what is your percent error? 4 5 3. Find the lowest and highest volume and subtract. Divide this answer by 2 to find the range. Record the average with the +/- value. Analysis: 1. Based on your percent error, discuss your accuracy. Use to specific values. 2. Based on your +/- value, discuss your precision. Use to specific values.