why is it dangerous to use water extinguishers in factories that use aluminum and magnesium?

Answer 1

Consider the reaction:

Mg + H2O ----> MgO + H2.

Putting water onto burning magnesium produces hydrogen gas, which isn't exactly going to put the fire out!

Answer 2

Water makes some fires worse, such as chemical fires or metal fires generally. Some metals, particularly those on the left side of the periodic table, can react quite violently with water and it is the water vapor in the air that causes metals such as sodium to self-combust if exposed to air - that's why they are stored in oil, for instance.

Class A extinguishers are for ordinary combustible materials such as paper, wood, cardboard, and most plastics. The numerical rating on these types of extinguishers indicates the amount of water it holds and the amount of fire it can extinguish.

Class D fire extinguishers are commonly found in a chemical laboratory. They are for fires that involve combustible metals, such as magnesium, titanium, potassium and sodium. These types of extinguishers also have no numerical rating, nor are they given a multi-purpose rating - they are designed for class D fires only. Class D extinguishers must be specifically suited for the potential type metal that might be combusted - different metals call for different compounds to extinguish them - and are typically dry powder type. Halon used to be the universal extinguishing agent but besides the fact it's an ozone destroyer, dangerous gases are formed when halon is used to put out fires. Wear proper respiratory equipment, particularly in enclosed spaces. After use, do not allow anyone to enter the area until it has been well ventilated. Halon extinguishers are no longer made but some may still be in use. Halon itself works by displacing oxygen so if you're caught in a room when it is filled with halon, hope your auxiliary breathing gear is working and you donned it properly.

Answer 3

"could scientists (and absolutely everyone else) go away room for the prospect that there is a mysterious clever "designer" or something unexplainable in the back of each thing we see?" No. If that's unexplainable, what variety of an answer is that? And no, identity would not carry any water. that's not even a medical concept. It does although carry water with those that have self assurance and recommend it, and that's the place it gets risky. human beings positioned their believe in those so-referred to as Christian scientists, basically to be grossly deceive.

Answer 4

magnesium reacts more aggresively with water when it is already in flames.