Lab equipment

I. Measuring and Dispensing Liquids Graduated cylinder 1. used to accurately measure volume 2. measured in mL 3. For the most precise measurements, use a graduated cylinder with the smallest marks 4. read it from the meniscus Meniscus – the curve at the surface of a liquid B. Pipettes, burettes, and syringes are also used for measuring volume and dispensing liquids

II. Handling and Storing Liquids A. Medicine dropper 1. generally, 20 drops will equal 1 mL 2. Not used to measure liquids precisely B. Test tubes 1. used for mixing and handling liquids 2. can be capped for storage C. Beakers and Erlenmeyer Flasks 1. used for storing and mixing liquids 2. Some have markings; however, they do NOT give accurate measurements 3. If it measures up to 250 mL of liquid, don’t use it to measure 250 mL of liquid because it could spill out

III. Measuring Mass & Weight A. Mass 1. measurement of how much matter is in an object 2. measured in grams 3. **use a triple-beam balance to measure mass** B. Weight 1. measurement of the force of gravity on an object 2. measured in Newton’s 3. Use a spring scale

C. Triple-beam balance 1. put it on a level surface 2 C. Triple-beam balance 1. put it on a level surface 2. make sure the riders are all the way to the left 3. Make sure the marker is at the zero mark 4. place your object on the pan 5. start with the largest rider 6. Move the riders until they click into place 7. add the numbers on the riders to find the mass D. Spring Scale 1. Used to measure weight 2. Hold the scale up and attach the object to the weighted hook

IV. Measuring Length & Temperature A. Meter stick Uses SI units (meters) to measure length B. Temperature A. measures how hot or cold an object is B. determined by how fast or slow an object is moving C. The faster the molecules are moving the higher the temperature D. kinetic energy – energy of motion E. Measure in degrees Celsius F. 100 degrees is boiling, 0 degrees is freezing (water)

V. Equipment Used for Heating A. Bunsen Burner A. uses gas to make a flame B. steps a. make sure the gas outlet handle is fully closed (at a 90 degree angle) b. connect the hose leading from the burner outlet to the gas outlet c. turn the handle on for the gas to open d. turn the gas adjustment knob at the base of the burner to allow gas through the burner e. hold a lighted match a little to the side of the gas flow f. Turn the air control vent to get a blue flame. The hottest part of the flame will be the top of the bright blue inner flame g. can reach temperatures up to 1500 degrees Celsius

C. Heating a test tube over a bunsen burner flame a C. Heating a test tube over a bunsen burner flame a. use a test tube clamp to hold the test tube by the body, not the rim b. never cap or plug a test tube when heating it c. always point the open end away from everyone d. don’t fill the test tube to the top e. don’t put the test tube in the hottest part of the flame

B. Hot plate A. Doesn’t produce an open flame B B. Hot plate A. Doesn’t produce an open flame B. never leave unattended C. Commonly used to heat liquids in beakers and flasks, esp. when ingredients need to be stirred

C. Heat Safety A. open flames and hot plates should never be left unattended B. Keep all flammable and combustible materials away from open flames C. Use appropriate equipment to handle hot glassware a. use test tube holders for test tubes b. Use tongs for beakers, flasks, or crucibles c. use asbestos gloves when handling hot glassware