Mass in Matter Measure the amount or total quantity of matter in an object Most common unit: _____________ SI unit of Mass: Kilogram

TIPS : MASS MEASUREMENTS USING A BALANCE  PICK UP WITH 2 HANDS!!!  FLAT SURFACE  CLEAN PAN  ZERO BALANCE

TIPS : MASS MEASUREMENTS USING A BALANCE  ALL RIDERS ARE SET AT “0”  DON’T LEAN ON THE TABLE  HANDS FREE!!!

TIPS : MASS MEASUREMENTS USING A BALANCE  MOVE RIDERS INTO NOTCHES  MOVE SMALLEST RIDER W/ PENCIL TIP OR ERASER  READ RIDERS AT EYE LEVEL

TRIPLE BEAM BALANCE ADJUSTMENT KNOB PAN RIDERS BEAM NOTCHES SCALE POINTER

TRIPLE BEAM BALANCE

PARTS OF BALANCE ADJUSTMENT KNOB PAN RIDERS BEAM NOTCHES SCALE POINTER

RIDERS MOVE RIDERS INTO NOTCHES MOVE SMALL RIDER WITH PENCIL TIP OR ERASER ADD ALL RIDERS TO GET FINAL VALUE! READ RIDERS AT EYE LEVEL

MASS Ways to Measure Mass: 1) Direct Place object on pan

MASS Ways to Measure Mass: 2) Indirect a) cup (Initial) b) cup + object (Final) c) find the difference = mass d) Final – Initial = mass of object (g)

Ways to Measure Mass: (TARE) 3) Pre-Set desired amount a) cup (measure to bal = 0) b) move riders to exact desired amount c) place object into cup until balance is at zero

Mass of Rock Triple Beam balance Indirect Mass to 2 decimal places (2 d.p.) 1.Measure the empty cup _______g 2.Measure the cup + obj _______g 3.Find the difference = mass of object Final – Initial = rock’s mass in grams

TRIPLE BEAM BALANCE WHAT NUMBER OF DECIMAL PLACES DO YOU REPORT?

CENT-O-GRAM BALANCE

DOUBLE PAN (TRIP) BALANCE BALANCE

DOUBLE PAN (TRIP) BALANCE WHAT CAN THE DOUBLE PAN BALANCE DO WITH 2 OBJECTS?

DOUBLE PAN (TRIP) BALANCE WHAT IS THE NUMBER OF DECIMAL PLACES TO REPORT HERE? HOW LOW CAN IT GO?

CENT-O-GRAM BALANCE WHAT IS THE NUMBER OF DECIMAL PLACES TO REPORT HERE? HOW LOW CAN IT GO?

CENT-O-GRAM BALANCE Designed for smaller objects in the chem lab

CENT-O-GRAM BALANCE HOW MANY DECIMAL PLACES CAN YOU REPORT?

ELECTRONIC BALANCE

ELECTRONIC IN USE? ADVANTAGES FAST EASY/SKILL VERY SMALL OBJ PRECISE SMALL STORAGE DISADVANTAGES 1 $$$ 2 POWER 3 EASILY DAMAGED 4 ONLY SMALL OBJ 5 ROOM CONDITIONS

Calibration To check the accuracy of an instrument with a standard!

Accuracy Closest to actual value

STANDARD An accurate tool to verify the measurement of another tool. Used to check the performance of a balance Bureau of Weights & Measures

Standards to calibrate!

Sensitivity What is the low /high for the instrument? What is the amount that is reliable? Reproducible? If measurements are different for different people…is it because of their precision or the sensitivity?

Precision People skill using the same tool Measurements that are close in value to each lab partner Reproducibility

TRUSTWORTHINESS YOUR RECORD IS TRUE ! SCIENTISTS DEPEND ON OTHER SCIENTISTS’ DATA TO BE ACCURATE AND PRECISE DON’T MAKE IT WHAT YOU THINK IT SHOULD BE MEASURE WITH SKILL (precision) PEER EVALUATION

DOUBLE PAN BALANCE (EQUAL ARM) TYPES OF OBJECTS SENSITIVITY/LIMITS EASE OF USE

TRIPLE BEAM BALANCE TYPES OF OBJECTS SENSITIVITY EASE OF USE

CENT-O-GRAM BALANCE HOW MANY DECIMAL PLACES CAN YOU REPORT?

CENT-O-GRAM BALANCE TYPES OF OBJECTS SENSITIVITY EASE OF USE

ELECTRONIC BALANCE TYPES OF OBJECTS SENSITIVITY EASE OF USE

TRIPLE BEAM BALANCE