If this is true then how do I take my aluminums temperature without fear of breaking the themometer and get mercury all over it?
Yes, okorder /... But I would not be afraid of taking the temperature of Aluminum...just be careful not to break the thermometer and it will be fine. Now-a-days, most common thermometers don't use Mercury anymore....it has been replaced with a colored alcohol which allows for colder temperatures to be measured as well as eliminates the possibility of a toxic substance being released upon breakage.
Butting any metal against any other with an electrolyte can cause electron exchange and corrosion. (Liquid mercury is its own electrolyte.)There are alternatives such as thermocouples that only have a ceramic in contact with the aluminum.
It's easy - don't use a mercury thermometer. In fact, don't use a liquid thermometer at all. Go solid state and use a contact thermocouple thermometer - cheap as sh*t and accurate to 0.1C. Or, if the temp is high and relatively inaccessible, use an infrared or laser pyrometer.
Yes, mercury corrodes aluminium. For this reason you're not allowed to carry it in your luggage on aircraft, in case it leaks and weakens the fuselage. If you rub it on an aluminium surface, it gets hot and reacts with the hard oxide coating that normally protects aluminium from further oxidation. If you try this experiment, wash your hands thoroughly afterwards, clean up any spilt mercury and use plenty of ventilation.
hang on ill have a psychic moment... ok, we have two types of metal. ferrous and non ferrous... ferrous rusts... Fe... iron. non ferrous... no iron... Copper and aluminium, and zinc and silver appear int he periodic table, they are NOBLE metals.. pure elements... copper corrodes in acid aluminium corrodes iin alkali and i dont know what corrodes Zinc... and theyre digging up pieces of silver and gold which are thousands of years old, out of the sea... and they look as good as the day they were made... oh, and raw untreated steel starts rusting within hours of exposure to water and air... without air, the metal willstill corrode, but it'll take much much longer... your average ford starts rusting itself to death within 10 years... yet the titanic has been under the ocean for almost 100 years... and ok, i know the titanic hull is a bit thicker than a ford wheel arch... but the principle holds.
