The bane of alkali is acid.
Extended data:
Because alkali reacts with acid to produce salt and water, the bane of alkali is acid.
Classification of alkali
1, according to the number of hydroxyl ions ionized by one alkali molecule: monobasic dibasic alkali polybasic alkali
2. According to solubility: soluble alkali, slightly soluble alkali and insoluble alkali.
3. According to ionization ability: strong base and weak base.
4. According to the purpose: industrial alkali and edible alkali.
Industrial alkali: industrial soda ash (sodium carbonate Na2CO3), industrial caustic soda (sodium hydroxide NaOH) and industrial heavy alkali (NaHCO3). The purity of industrial alkali and the content of impurities (which may contain heavy metals) can meet the general industrial use, and the process is relatively simple, which can be used for large-scale industrial production and is harmful to human body.
Edible alkali: edible soda ash (sodium carbonate Na2CO3, with the same molecular formula, but without impurities of industrial soda ash) and edible baking soda (sodium bicarbonate NaHCO3).
The chemical properties of alkali are ***5, also known as the universality of alkali. It should be noted that some properties only apply to soluble alkali.
1, alkali solution can interact with acid-base indicator:
Alkali solution turns blue when it meets purple litmus test solution (the phenomenon is not obvious, but it changes), and turns red when it meets colorless phenolphthalein solution (the phenomenon is obvious);
2. Alkali can react with nonmetallic simple substance: disproportionation reaction between chlorine and alkali;
3. Alkali can react with acid to produce salt and water (this kind of reaction is usually called neutralization reaction, which releases a lot of heat △ H = 57.3 kJ/mol);
4. Alkali solution can react with acid oxides to generate salt and water;
5. Alkali solution (relatively strong alkali) can react with salt to generate new alkali (relatively weak alkali) and new salt.
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