It is produced by burning iron wire in oxygenFe3O4The temperature of the solid is very high and when it splashes the bottom of the collecting bottle of gas, it bursts easily. the bottom of the bottle. The purpose of putting water first or spreading a layer of fine sand at the bottom is to prevent the splashed solid ferric oxide from exploding the gas cylinder.
The phenomenon of burning iron wire in oxygen is as follows: violent combustion, sparks flying out, forming a black solid and releasing a lot of heat. The iron wire burns in oxygen to produce ferric oxide. The literal expression of this reaction is: iron + oxygen ignites ferric oxide.
Remarks
1. The wire burns in oxygen. During the experiment, a match should be attached to the wire. Its function is to ignite the wire.
2. The wire is wound into the shape ofspiral. Its function is to increase the contact area between the iron wire and oxygen and to increase the local temperature of the iron wire as quickly as possible.
3. The change in the semi-molten state of the iron wire after it is cooked is only a change in the state of the iron, no new substances are generated, and it is a physical change.
Text expression of the combustion of an iron wire
Experiment of combustion of an iron wire in oxygen
< p>The chemical equation is: 3Fe+2O? = Ignition = Fe?O?Phenomena: The iron wire burns violently, sparks are emitted, a black solid is generated, and heat is released;
Remarks: ① Polish the wire iron with sandpaper; ② Wind the fine iron wire into a spiral shape, the purpose is to increase the contact area between the iron wire and oxygen. ③ A match is attached to the lower end of the iron wire, which is used to ignite the iron wire; threadof iron. ④ When the match is almost burned out, extend the iron wire into the gas cylinder to avoid burning the oxygen in the cylinder. ⑤ Put a small amount of water at the bottom of the gas collection bottle to prevent gas from appearing. high temperature melting caused by splashing and explosion of the bottom of the gas collecting bottle can also be used instead.
Text expression for wire combustion:
Iron + oxygen → ferric oxide (condition is Fe ignition +O2=); ignite = Fe3O4. The phenomenon is as follows: violent combustion, sparks fly, a black solid is produced, and a large amount of heat is emitted. Wire is a kind of metal wire made of iron. The composition of the wire varies depending on its use. It contains: iron, cobalt, nickel, copper, carbon, zinc and other elements.
Iron is an elementmetallic with an atomic number of 26. Its elementary chemical formula is Fe and its English name is iron. The average relative atomic mass is 55.845. Pure iron is white or silvery white and has a metallic luster. It has a melting point of 1538°C and a boiling point of 2750°C. It is soluble in strong and moderately strong acids, but insoluble in water. Iron has a price of 0, a price of +2, a price of +3, a price of +4, a price of +5, and a price of +6. Among them, price +2 and price +3 are more common, and price +4, price +5 and price +6. prices are rare.
Iron is widely distributed in life, accounting for 4.75% of the earth's crust, ranking fourth after oxygen, silicon and aluminum.
Pure iron is a flexible, ductile silver-white metal used toIt is used to make the iron core of generators and electric motors. Iron and its compounds are also used to make magnets,medicines, inks, pigments, abrasives, etc. It is one of the “black metals” of the industry (the other). two are chromium and manganese) (In fact, pure cast iron is silvery white. Iron is called "black metal" because the surface of iron is often covered with a protective film whose main component is iron black iron oxide).
In addition, the human body also contains iron. The +2 valence ferrous ion is an important component of hemoglobin and is used for oxygen transport.