The main reason for rust is that iron metal reacts with water and oxygen in the environment in the presence of impurity carbon, and iron metal will rust. Used in paint, ink, rubber and other industries, can be used as a catalyst, glass, precious stones and metal polishing agent, and can also be used as iron-making raw materials. The biggest use of iron oxide is as a pigment.

According to the color, it is divided into iron oxide red, iron oxide yellow and iron oxide black, and iron oxide brown is formed by mixing iron oxide red, iron oxide black (and iron oxide yellow); Iron oxide orange is a mixture of iron oxide red and iron oxide yellow. Iron oxide green is a mixture of blue phthalocyanine and iron oxide yellow.

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Stability of iron oxide: stable, soluble in hydrochloric acid and dilute sulfuric acid to form iron salt. Elemental iron generates ferrous ions in the displacement reaction.

1, iron metal is one of the most widely distributed metals on the earth. It occupies about 5. 1% of the earth's crust, ranking fourth in the element distribution sequence, second only to oxygen, silicon and aluminum.

2. Iron is a shiny silvery white metal, hard and malleable, with melting point 1535℃ and boiling point of 3000℃. It has strong ferromagnetism, good plasticity and thermal conductivity. The specific heat capacity is about 0.46* 1000J/KG*℃?

3. Iron metal is taken from iron ore. Limestone, coke and iron ore are put into the blast furnace in layers, and high-temperature airflow is blown from the bottom to make the coke turn hot and red, so iron is reduced from the oxide, melted into liquid state and flows out from the bottom.

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