49. What is the main component of the wet-process flux?

The commonly used "wet-process" fluxes primarily consist of two types: one employs ammonium chloride (NH₄Cl) as the sole flux, while the other uses a mixture of ammonium chloride and zinc chloride (ZnCl₂·2NH₂Cl or ZnCl₂·3NH₄Cl) as the flux. Additionally, additives such as glycerol (approximately 6% of the flux weight) or glycerol propanol (about 1% of the flux weight) are often incorporated. Some formulations also include wood chips or sugars as foaming agents to retain moisture within the flux.