Project | Indicator | ||||||
I | II | ||||||
HF-J-40 | HF-I-55 | HF-I-70 | HF-II-30 | HF-II-40 | HF-II-50 | HF-JI-55 | |
Hydrofluoric acid (HF) w/% | 40.0 | 55.0 | 70.0 | 30.0 | 40.0 | 50.0 | 55.0 |
Fluorosilicic acid (H2SiF6) w/% | 0.05 | 2.5 | 5.0 | 8.0 | 10.0 | ||
Non-volatile acid (H2SO4) w/% | 0.05 | 0.08 | 0.08 | 1.0 | 1.0 | 2.0 | 2.0 |
Ignition residue w/% s | 0.05 |


First of all, from the description of the title, we can learn some basic physical properties of hydrofluoric acid: it is a colorless, clear, smoke-emitting corrosive liquid, and has a sharp pungent odor. These properties describe the appearance, state, and smell of hydrofluoric acid and are the basis of our understanding of this substance.

Next, the question mentions the different concentrations of hydrofluoric acid and their corresponding uses. 40% of hydrofluoric acid can be used for cleaning, which may be due to its certain dissolution and cleaning capacity. 55% hydrofluoric acid can be used for etching glass, engraving patterns, marking scales and writing. This is because hydrofluoric acid can react with the silica in the glass to achieve the etching of the glass. This property makes hydrofluoric acid in glass processing, art production and other fields have a wide range of applications.


