By Wenzhong Zhang
According to Wikipedia, a laboratory (informally, lab) is a facility that provides controlled conditions in which scientific or technological research, experiments, and measurements may be performed [1]. Contrary to most people’s understanding, laboratory is definitively not a mysterious place. My understanding is that the chemistry lab and our normal household kitchen are half siblings. You can easily find the majority of lab equipment lying in your kitchen, of course, in a similar but not exact same form. Herein I will demonstrate the common kitchenware and their “brothers and sisters” in a chemistry lab.
Mixing – Kitchen mixer vs. magnetic stirrer
Kitchen stand mixers are very helpful especially when preparing flour-based food and foaming cream or egg white. The motor stirs the mixer continuously and all you need to do is add, add, and add. In this case, the beater gets into contact with the mixture and stirs them using mechanical forces. During chemistry experiments, mixing is usually provided by magnetic stirrer and a Teflon-coated magnetic stirring bar. The stirrer generates alternating magnetic field and therefore provide the magnetic force for the stirring bar to spin. Direct contact between the stirring machine and the solution is avoided mainly because the solution can be highly corrosive. The poor wettability and reactivity of Teflon makes it an excellent coating material for the stirrer.
Measuring – Table spoons vs. pipettes
Table spoons are rough volume measuring tools yet they are sufficient enough for cooking. One US table spoon equals approximately 15 milliliters. In scientific research, accuracy is highlighted and spoons are usually not accurate enough. Pipettes work by creating a partial vacuum above the liquid-holding chamber and selectively releasing this vacuum to draw up and dispense liquid [2]. Their accuracy and range are designed and calibrated to meet the everyday liquid handling needs of experiments.
Ventilation – Exhaust hood vs. Fume cupboard
Ventilation is necessary when you are frying fries or cooking oily stuff. Exhaust hoods use a mechanical fan to remove as much as possible the fume generated. Still, you can smell the mouth-watering flavor of the food. However, the smell of a chemical can be sometimes toxic in a chemistry lab. Chemists work in fume cupboards and all the gases generated are effectively pumped outside into a filtering system, then to the top of the building. This is particularly important when acids or flammable stuff are used. The filtering system will absorb all the toxic chemicals and it is replaced whenever needed.
Water – Tap water vs. pure water
Tap water is usually good for cooking and cleaning. Some people might use filtration system or water pitchers to get rid of partly the hardness (calcium and magnesium content) in water. For scientific research, in most of the cases, tap water can be only used for initial washing. The reactions and analysis utilize typically deionized water, distilled water or super pure water. Normally, each lab has a pure water machine that generates water to an extremely high standard of purity by means of ultrafiltration, reverse osmosis. etc.
Waste sorting – For recycling vs. For safety
Household wastes are sorted into biowaste (goes to fermentation), plastic waste (of course goes to plastic recycling), metal waste (same), paper and carton (same), and mixed waste (landfill). The idea is that most of the recyclable waste can be sorted and recycled, leaving very limited amount for burning and landfilling. Waste water are poured into the sink and goes to municipal waste water treatment plant. In the laboratory, wastes are handled in a completely different way. In most cases, laboratory wastes are not allowed to be recycled because of the potential toxicity. Organic wastes, acid wastes, heavy metal wastes, glass wastes, needle wastes, etc. are all sorted extensively and delivered to special company for handling.
Being a chemist and also an enthusiastic cook, I always say that:” I have a dream, that one day I will have a set of pipettes in my own kitchen. I will make salts and sugars into 1 M solution and pipette the exact amount for cooking.” Dream is always a dream.
[1] https://en.wikipedia.org/wiki/Laboratory[2] https://en.wikipedia.org/wiki/Pipette