Reaction equation of potassium dichromate and potassium iodide under acidic conditions

Reaction equation: k? Cr？ o？ +6KI+7H？ So what? =Cr？ (So? )? +7H？ O+3I？ +4K？ therefore

This reaction usually uses sulfuric acid under acidic conditions, because together with hydrochloric acid, chloride ions will also react with potassium dichromate, while nitric acid will oxidize iodine ions.

Potassium dichromate is an orange-red triclinic or acicular crystal at room temperature, which is soluble in water and insoluble in ethanol, also known as potassium dichromate. Molecular formula: K2Cr2O7, molecular weight 294. 1846, melting point: 398? C. boiling point: 500? Potassium dichromate is a toxic and carcinogenic strong oxidant.

Potassium iodide has good solubility and can be atomized and sprayed on dry salt. However, its chemical properties are unstable, and the salt will fail due to moisture or exposure to humid air, light, heat, acidic environment, impurities and other factors.

Potassium iodide is very unstable if it is strengthened with crude salt with low purity. If the woven bag containing salt gets wet, potassium iodide will dissolve and adsorb on the bag, which will eventually lead to the loss of iodine.

In order to avoid the loss of iodine as much as possible, the purity of salt should be higher than 99.5%, the water content should be lower than 0. 1%, and stabilizers and desiccants should be added. Generally speaking, potassium iodide has poor environmental adaptability.

Extended data

Use:

1, potassium iodide is often used as corrosion inhibitor for steel pickling or synergist for other corrosion inhibitors. Potassium iodide is the raw material for preparing iodide and dye. Used as photographic emulsifier and food additive, used as expectorant and diuretic in medicine, used as medicine for preventing and treating goiter and hyperthyroidism before operation, and also used as analytical reagent. It is used as a photosensitive emulsifier in the photographic industry and also as a drug and food additive.

2. Used as feed additive. As a component of thyroxine, iodine participates in the metabolism of all substances in livestock and poultry and maintains the heat balance in the body. Iodine is an essential hormone for the growth, reproduction and lactation of livestock and poultry, which can improve their growth performance and promote their health.

If there is iodine deficiency in livestock and poultry, it will lead to metabolic disorder, organism disorder and goiter, which will affect nerve function, coat color and digestion and absorption of feed, and eventually lead to slow growth and development.

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