LABORATORY EQUIPMENT Balances Most solutes are measured on

LABORATORY EQUIPMENT

Balances • Most solutes are measured on a balance in grams or milligrams (0. 001 g) • Balances are electronic or analytical • Electronic Balances measure mass or weight of the substance • A boat or balance paper is always used on a balance to protect the pan

WEIGHING PROCEDURE : • WEAR GLOVES & EYE PROTECTION WHEN WORKING WITH CHEMICALS • LEVEL THE BALANCE & TURN IT ON. • SELECT THE WEIGHT UNIT (MILLIGRAM OR GRAM). • VERIFY THE READING IS ZERO. • PLACE PAPER OR PAN / BOAT ON SCALE. • RE-ZERO THE DISPLAY. • PLACE THE SUBSTANCE / OBJECT IN THE PAN OR ON THE PAPER WITH A SCOUP. • WHEN THE READING IS STABLE; RECORD THE WEIGHT. • TURN OFF THE BALANCE SCALE. • REMOVE THE PAPER OR PAN.

CENTRIFUGE IS AN INSTRUMENT USED TO SPIN SAMPLES AT A HIGH RATE OF SPEED. USES FORCE TO SEPARATE SUSPENSIONS (HEAVIER & LIGHTER SUBSTANCES). MICROCENTRIFUGE- SPINS &SEPARATES VERY SMALL VOLUME IN MICROTUBES

USING A CENTRIFUGE 1. PLACE CENTRIFUGE ON A LEVEL SURFACE 2. FILL TUBE & SEAL TOP 3. FILL MATCHING BLANK BALANCE TUBE 4. PLACE TUBES IN TUBE WELLS DIRECTLY ACROSS FROM EACH OTHER 5. CLOSE LID & SECURE 6. SET TIMER & SET SPEED ADJUSTMENT (VARIES) 7. TURN CENTRIFUGE “ON” 8. REMOVE TUBE & BLANK WHEN COMPLETE 9. CLOSE LID & REPLACE ALL SUPPLIES

p. H METER is an Instrument used to test the degree of acidity or alkalinity of a solution. • The p. H Scale goes from 0 – 14 • 1 -6 = acid, 7 = neutral, 8 -14 = alkaline

USING A p. H METER 1. 2. 3. 4. 5. 6. Turn on p. H Meter (Use caution with electrode) Rinse off electrode with distilled H 2 O Set temperature setting to room temp. (optional) Place electrode in p. H 7 buffer standard (swirl) Rinse electrode with distilled H 2 O Use buffer standards to calibrate electrode: (strong acid – p. H 4 buffer or strong base – p. H 10) 7. Place electrode in solution, read & record