What are red powder and black powder in junior high school chemistry?
1, iron oxide: also known as limonite, pyroochre, iron Dan, iron red, red powder, Venice red (mainly iron oxide), etc. , the appearance is reddish brown powder. Its reddish-brown powder is a low-grade pigment, which is called iron oxide red in industry and is used in paint, ink, rubber and other industries.
2. Copper: Copper is a non-ferrous metal closely related to human beings. Widely used in electric power, light industry, machinery manufacturing, construction industry, national defense industry and other fields. Second only to aluminum in the consumption of non-ferrous metal materials in China.
3. Red phosphorus: Red phosphorus is a huge covalent molecule with amorphous structure. Purple amorphous powder, odorless, metallic luster, no phosphorescence and odorless in the dark. Insoluble in water and organic solvents, such as carbon disulfide and ethanol.
4. Cuprous oxide: Cuprous oxide is an oxide of monovalent copper, a bright red powdery solid that is almost insoluble in water. It is disproportionated into divalent copper and copper simple substance in acidic solution, and gradually oxidized into black copper oxide in humid air.
5. Iron hydroxide: it is brown or reddish brown powder or dark brown flocculent precipitate or colloid, which is used to make pigments and drugs, as a water purifying agent (when colloid is used) and as an antidote to arsenic.
Black powder in junior high school chemistry is:
1, iron powder: the aggregate of iron particles with particle size less than1mm. Color: black. It is the main raw material of powder metallurgy. According to the particle size, it is customarily divided into five grades: coarse powder, medium powder, fine powder, fine powder and superfine powder. Iron powder consisting of particles with particle size of 150 ~ 500μ m is coarse powder, medium powder with particle size of 44 ~ 150μ m, fine powder with particle size of 10 ~ 44μ m, ultrafine powder with particle size of 0.5 ~ 10μ m and ultrafine powder with particle size less than 0.5μm m. ..
2. Carbon: black powdery or granular porous crystal. Carbon is a very common element, which exists widely in the atmosphere, crust and living things in various forms.
3. Copper oxide: It is a black oxide of copper, slightly amphoteric and slightly hygroscopic. The relative molecular weight is 79.545, the density is 6.3 ~ 6.9 g/cm3, and the melting point is 1026℃.
4. Manganese dioxide: black amorphous powder or black diamond crystal. Solubility: insoluble in water, weak acid, weak base, nitric acid and cold sulfuric acid, but soluble in concentrated hydrochloric acid under heating to produce chlorine gas.
5. Fe3O4: commonly known as iron oxide black, magnet, magnet and black iron oxide, it is a magnetic black crystal, so it is also called magnetic iron oxide.
References:
Iron oxide-Baidu encyclopedia