SEC 1 3 DESIGNING YOUR OWN LAB DESIGNING
SEC. 1. 3 - DESIGNING YOUR OWN LAB
DESIGNING LABS • The following strategies are in place to help you get used to designing and writing your own labs- they are hints that will help you stay focused on the goal/purpose when designing a lab to allow you to write them more efficiently
• Gives you a plan of attack- you can adjust it as you need to for different labs or your own personal preference.
FIRST- IDENTIFY THE PURPOSE, PROBLEM, OR QUESTION • If variables are involved (relationship or effect lab), identify them in the problem Ex of purpose with variables: To determine the effect of temperature on pressure • Identify any important constants
• If variables are not involved, be as specific as possible (what conditions are the lab performed under? ) Example Question: What is the concentration of a saturated Na. Cl solution at room temperature?
GATHER BACKGROUND INFORMATION • This section of a lab is for you to include any information you know that may pertain to the purpose, problem, or question. This information is what you will use to help make conclusions
• Background Info may contain: Definitions Known relationships Equations
WRITE A HYPOTHESIS • Only write a hypothesis if the lab contains variables- a relationship or cause/effect lab • After looking at your background info- write a hypothesis • Remember- A hypothesis is not JUST a prediction- it is a prediction with an explanation
SET UP RESULTS/CALCULATIONS SECTION • Write any equations you will need to solve your problem or answer your question
• You won’t have numbers to plug in yet, but you can set everything up in advance so all you have to do is plug them in
SET UP THE DATA TABLE • You definitely want to do this before you start the lab so you can record all your data when you need to • you don’t want to have to rush to make a data table while you are running your experiment because you might miss something
• Go through the calculations section you made and make a table that includes spaces for each quantity you will need
• Remember, some measurements need to be made indirectly Ex: You can’t put chemicals directly on a balance, so you will need the mass of the empty container (beaker, flask, weighing dish), and the mass of container and chemical in your data table
DATA TABLE- FOR DATA, NOT CALCULATIONS • Your data table should NEVER include any calculated values- even if you’re just doing simple subtraction • Remember- data are collected measurements made with instruments, or observations
WRITE YOUR PROCEDURE • Good procedures should be: Clear, concise, numbered list of steps Repeatable- by someone of your level of experience/education • While writing the procedure- go through your data table and make sure you have a step to measure each thing your table asks for
• If the data table includes masses or volumes of chemicals, give an approximate amount in the procedure Ex: Add approximately 2 g of Na. Cl to the beaker. Find exact mass and record
WRITE YOUR MATERIALS LIST • Go through your procedure and make a list of each piece of equipment and chemical that you will need • Include the quantity of each piece of equipment, and approximate quantity of chemical
WRITE YOUR SAFETY CONCERNS • Go through your procedure and materials and specify any safety concerns
• Possible Safety Concerns: Wear goggles (any time your use chemicals or use glassware) Use caution with glassware Use caution with hot glassware or hot chemicals Any specific cautions to a chemical you’re using (teach will tell you these) Report any spills, breaks, or incidents to
CONCLUSION • Restate the purpose, problem, or question • Completely answer the purpose, problem, or question with your results
• If you made a hypothesis- address it… does your data/results support or not support it? • Suggest possible sources of error“human error” is not specific enough, and “calculations” doesn’t count
SAMPLE PROCEDURES • Mrs. Porter will pass out examples of certain procedures- some are poorly written, some are well written • Write down feedback on each procedure- is it clear, specific, repeatable? What are the strengths/weaknesses? • Discuss with your group and rank these from “worst” to “best”, and be ready for class
NOW YOU’RE READY! • Mrs. Porter will check your procedures for any errors to assure you will be safe and successful • It is okay to make changes to your procedurethe first go round is never perfect- just make sure you record those changes and okay them with Mrs. Porter • Record all data in data table and complete the
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