Test Tube Racks

Truck-fender liners, drinking cups, juice and dairy-product containers and lids, test-tube racks... 

Label three test tubes 1, 2, and 3. Place all four test tubes in a test-tube rack. 

M hydrochloric acid (HCI) test tubes (6) test-tube rack... 

M sodium chloride (NaCI) 0.2M sodium sulfate (Na2S04) 0.2M sodium sulfite (Na2S03) 0.2M lead(ll) nitrate (Pb(N03)2) 0.2M zinc nitrate (Zn(N03)2) test tubes (10) test-tube racks (2) thermometer 10-mL graduated cylinder... 

Place the test tube containing the magnesium in a test-tube rack and add ten drops of 6M HC1. Record in Data Table 1 any observations during and immediately following the reaction. CAUTION Do not inhale vapors or look down into test tube. Observe the reaction from the side of the test tube. 

M sodium hydroxide (NaOH) (5 mL) red litmus paper boiling chips hot plate 250-mL beaker 10-mL graduated cylinder test tubes (8) test-tube rack stirring rod dropper beaker tongs... 

After 5 minutes of heating, remove the test tubes and place them in the test-tube rack to cool. Record your observations in Data Table 1. Note any color changes or precipitate that formed. Benedict s solution contains an oxidizing agent... 

How can you make a polyester and a polyamide Objectives Prepare a polyester from phthalic anhydride and ethylene glycol. Prepare a polyamide from adipoyl chloride and hexamethylenediamine. phthalic anhydride (2.0 g) sodium acetate (0.1 g) ethylene glycol (1 mL) 5% adipoyl chloride in cyclohexane (25 mL) 50% aqueous ethanol (10 mL) 5% aqueous solution of hexamethylenediamine (25 mL) 20% sodium hydroxide (NaOH) (1 mL) scissors copper wire test tube test-tube rack 10-mL graduated cylinder 50-mL graduated cylinder 150-mL beakers (2) ring stand clamp Bunsen burner striker or matches balance weighing papers (2)... 

Using a china marker, label five test tubes as follows and place them in the test-tube rack. Label test tube 1, Unknown test tube 2, 0.0M NaN03 test tube 3, 0.3M NaN03 test tube 4, 0.6M NaN03 and test tube 5, 0.9M NaN03. 

Eric Niedergeses examines atesttube forthe presence of a yellow precipitate to confirm that the contents of a drum is tribasic calcium phosphate. Test tubes representing other drams are in the test tube rack on the bench in front of Eric. 

Obtain a test tube rack and 11 small test tubes. Add distilled water to each tube such that each is about a fourth to a third full. Place a piece of labeling tape on each. 

Obtain small samples of NaCl, CaC03, Fe203, A1203, and the metals aluminum, zinc, iron, copper, and silver. Obtain around 20 small test tubes and a test tube rack Place a piece of labeling tape on each tube. 

Obtain and clean 12 test tubes large enough to be able to dip a combination pH electrode into a solution held inside it. Also obtain one or two test tube racks to accommodate the 12 test tubes. Label ten of the test tubes as follows pH3, pH4, pH5, pH6, pH7, pH8, pH9, pHIO, pHll, and pH12. Label the remaining two as follows 0.5 M HC1 and 0.5 M NaOH. Fill these with the appropriate solutions. Place all test tubes in the rack. 

Materials test tube, test-tube rack, 10-mL graduated cylinder, hydrochloric acid, magnesium ribbon, sandpaper, cardboard, wood splint, safety matches... 

Place your test tube in a test-tube rack. For safety, the test tube should remain in the rack throughout the lab. 

RACKCLEARl - position far enough above the test tube rack in preparation for manipulation and hand descent... 

Test tube rack (or tall form beaker)... 

Place the test tube in a test tube rack or a beaker. Note the time and expose the test tube to sunlight. From time to time, note the time and observe the progress of the polymerization (see Note 3). 

Depyrogenated soda-lime (flint) 10 x 75 test tubes Depyrogenated borosilicate 13 x 100 mm test tubes Test tube rack... 

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