Sam Barros’ ChemLabs!

The more hazardous items are kept in a cupboard for added safety. The acids and bases come in large bottles; the brown ones are for light sensitive chemicals such as hydrogen peroxide and nitric acid, and the large heat resistant 1L graduated Schott Duran for Sulphuric. The smaller bottles (250, 100, and 50mL) contain chemicals that are not used frequently, are very expensive, or are too hazardous for mass storage (examples include mercury metal, sodium peroxide, phosphoric acid, arsenic, etc). Oxidizers and solids in general come in plastic bottles ranging from 25g to 1kilogram. The Hydrofluoric and Perchloric acid, and the distilled water all come in Teflon bottles. These feel like they are constantly covered in oil or butter, due to the extremely low coefficient of friction of PTFE.

Some of the glassware includes Beakers (50, 100, 150, 250, 300, 400, 500, 600, 800, 1000mL, two of each), Erlenmyer flasks (2x 50, 2×100, 250, 1000mL), Filtration flasks (250 and 150mL), Test tubes (200x20mm and 15x10mm, 8 of each, all with accompanying rubber corks), glass balloons (100, 250mL), flat bottom flasks (50, 100, 150mL), buchner funnel, decanting flasks, glass funnels, hourglasses of assorted sizes (10), alumina ceramic mortar and pestle (250 and 600cc), glass pipettes (2×10, 25, 50 and 100mL), pipette pumps, titration pipette, thermometers (-10 to 250C mercury and 2 alcohol ones from -30 to 150C), pincers (3), scalpels (3), glass stirrers, boiling beads, metal spoons and spatulas, and many others. All this glassware was manufactured in Germany, and is “Duran”, by Schott. This is the highest quality glassware I have ever seen, as it is even more heat resistant than Pyrex. I only managed to break one piece of glassware by thermal shock so far (the Sodium Peroxide experiment above shows how it happened). It also withstands impact better than regular glass, though I have always been extremely careful not to drop them because of their price (several times that of ordinary glassware).
For the hydrofluoric acid experiments a 1L polyethylene beaker was obtained. It held up O.K. but became permanently stained; unfortunately Teflon beakers could not be obtained for the purpose of those experiments, even though they would be more appropriate.

Some of the more “advanced” equipment includes a 0 – 360C thermostat controlled hotplate (300W), a 50cm long serpentine glass condenser (both seen on the picture to the left, which show a distillation apparatus set up for the distillation of Nitric Acid. Not show in the apparatus is the venturi pump and vacuum line, which was necessary for reduced pressure distillation). The picture to the right shows a vacuum dissector. It consists in a 10L glass vessel weighting over 15kilograms, containing 2 kilos of Silica Gel in the bottom, and attached to a vacuum pump. A substance to be dried is placed inside the dissector and a vacuum is pulled inside it with the attached pump (in this picture a refrigerator pump is being used. This worked reasonably well and could dry most things within a couple of hours). As the water evaporates from the material it becomes trapped in the silica gel. Once the silica has become saturated (evidenced by it change of color from blue to pink, thanks to a cobalt indicator added to it) it needs to be heated at 150C for a couple of hours so it can once again perform its duty. This dissector greatly increased the speed of the procedures in the lab, making procedures that require multiple crystallizations take hours, as opposed to days. It was found that Silica can absorb most solvents almost as well as water, though it deteriorates quicker in doing so.

I was fortunate enough to find someone to buy my chemicals once I moved out of Sao Paulo and could not take them along with me to USA. Shown above are two of the six boxes in which they were put. The box to the right contains fluorescein, and miscellaneous fuels. The box to the right contains mostly acids, from which I can identify 9 litres of 99.8% analytical grade Sulphuric Acid, 10 litres of 68% analytical grade Nitric Acid, and a half kilogram bottle of  Benzoyl Peroxide (stabilized by the addition of 20% water). There are also some oxidizers in the box.

Not shown also are all the safety equipment required for working with some of the hazardous chemicals above. These include an organic vapor-rated activated carbon filter gas mask, polycarbonate goggles, face shield, nitrile gloves, fume cupboard, fire extinguisher, earmuffs, and others.