Calibrated Glassware
Calibrated Glassware – Read about Pressure Gauges Calibration Apparatus
| 1 | Beakers of different sizes | Different sizes, Clibrated |
| 2 | Conical flasks of different sizes | Different sizes, Clibrated |
| 3 | Vaccum filtration assembly | Different sizes, Clibrated |
| 4 | Graduated cylinders of different sizes | Different sizes, Clibrated |
| 5 | Test tube stands of different sizes with stands | Different sizes, Clibrated |
| 6 | Funnels of different sizes | Different sizes, Clibrated |
| 7 | Burretts of different sizes | Different sizes, Clibrated |
| 8 | Pippetts of different sizes | Different sizes, Clibrated |
| 9 | Dropers of different sizes | Different sizes, Clibrated |
| 10 | Molar flasks of different sizes | Different sizes, Clibrated |
| 11 | Bottles and jars of different sizes | Different sizes, Clibrated |
| 12 | Ptri dishes of different sizes | Different sizes, Clibrated |
| 13 | Stirrers | Different sizes, Clibrated |
| 14 | Crucible of different sizes | Different sizes, Clibrated |
| 15 | Watch glasses | Different sizes, Clibrated |
| 16 | Separatory funnels of different sizes | Different sizes, Clibrated |
| 17 | Condensers of different sizes | Different sizes, Clibrated |
| 18 | Boiling flasks of different sizes | Different sizes, Clibrated |
| 19 | Buchner Funnel of different sizes | Different sizes, Clibrated |
| 20 | Thermometers | Different sizes, Clibrated |
| 21 | Centrifuge Tubes | Different sizes, Clibrated |
| 22 | Gas syringes of different sizes | Different sizes, Clibrated |
| 23 | Heat exchangers | Different sizes, Clibrated |
| 24 | Soxhlet Extractors | Different sizes, Clibrated |
| 25 | Cuvettes | Different sizes, Clibrated |
| 26 | Desiccators | Different sizes, Clibrated |
| 27 | Evaporating dishes | Different sizes, Clibrated |
| 28 | Sublimation apparatus | Different sizes, Clibrated |
| 29 | Ubbelohde viscometer | Different sizes, Clibrated |
| 30 | Vial | Different sizes, Clibrated |
| 31 | Wash bottle | Different sizes, Clibrated |
| 32 | Weighing bottle | Different sizes, Clibrated |
| 33 | Distillation apparatus | Different sizes, Clibrated |
Determination of calcium carbonate dispersing power (threshold effect)
Principle
The products to be tested are titrated with a calcium acetate solution in the presence of carbonate ions.
The amount of calcium carbonate inhibited per gram of test product is calculated.
The test provides an indication of the strength of the threshold effect (CaCO3 dispersing power) of chemicals based on polyacrylic acids.
Chemicals and apparatus
Glassware: 250-ml beakers (not less than 3 per test substance),
several pipettes, measuring cylinders, etc.
Chemicals: sodum carbonate (soda) 2 % solution
calcium acetate, anhydrous 2 % solution
caustic soda (solid) 3 % solution
Water: de-ionized or distilled
Apparatus: pH meter
magnetic stirrer
Procedure
2 g test substance is weighed into a 250-ml beaker, dissolved in
50 ml de-ionized or distilled water and the solution is
adjusted to pH 8 with caustic soda 3 % while being stirred.
10 ml soda solution 2% is stirred in, the mixture is made up to 150 ml
and adjusted to pH 11 with caustic soda 3%.
Phase 1: Preliminary titration
The amount (ml) of calcium acetate solution which causes permanent turbidity of the test solution is first determined for each product.
Phase 2: Main titration
To confirm the preliminary titration results, further tests are carried out with a series of linearly graduated amounts (ml) of calcium acetate solution, the mid-point of the series being the amount (ml) found from the preliminary titration. –> see example
Increments of 4 ml are suggested.
Important: The weighed amount used for this titration should be enough to consume
20 – 30 ml calcium acetate solution.
| Example Prelim. titration: weighed amt. = 2.0 g actual consumption = 60 ml Main titration: weighed amt. = 0.8 g calc. consumption = 24 ml The main titration is hence performed with :20 ml, 24 ml and 28 ml. |
| Important: As the reaction is time-dependent, the time varying with the product, wait one hour before definitive assessment ! |
| In this case the end-point of the titration is at 24 ml calcium acetate solution Calculation The amount of calcium that can be inactivated per gram of product and/or the maximum water hardness for which 1 g/l is enough is calculated. Important : 1ml of the 2 % calcium acetate solution contains 5.067 mg Ca |
| Maximum amount of Ca that can be inactivated per gram of product: | mg Ca / g = 5.067 x cons. Ca acetate in ml weighed amount |
| Maximum water hardness for 1 g product: | °dH* / g = 0.7 x cons. Ca acetate in ml weighed amount |
