Moderately alkaline food: dried radish, soybean, carrot, tomato, banana, orange, pumpkin, strawberry, protein, dried plum, lemon, spinach, etc.
Generally speaking, the alkalinity of a substance depends on its ability to accept protons and the stability of the atomic groups formed. For example, NH3 can accept BF3 to form BF3+NH3-, and NH3 can accept H+ to form NH4+, but the stability of this ion is poor, so NH3 is weakly alkaline. While NH2- accepts H+ to form stable NH3, so NH2- is strongly alkaline. In aqueous solution, NaOH is as alkaline as KOH.
The stronger the metallicity of an element, the stronger the alkalinity of the hydrate of its highest valence oxide; The stronger the nonmetal of elements, the stronger the acidity of the highest valence oxide hydrate.
The alkalinity of some compounds can also be expressed by the content of O2- negative ions. For example, the alkalinity of some industrial slag is expressed by the activity of O2- negative ions.