Chemical activity refers to the ease with which a substance undergoes a chemical reaction. Ammonium metatungstate (AMT) exhibits chemical activity primarily through its decomposition and transformation behavior under acidic conditions and thermal treatment. As a precursor to tungsten compounds, AMT plays a vital role in industrial applications and chemical synthesis.

Specific surface area refers to the total surface area per unit mass of a substance, typically measured in m²/g or m²/kg. For ammonium metatungstate (AMT) powder, this includes not only the external surface area of the particles but also the surface area of internal pores, cracks, and other microstructural features. This parameter directly reflects the degree of dispersion and surface activity of the material—finer particles or greater porosity result in a larger specific surface area.

Ammonium Metatungstate (AMT) is a white crystalline powder that is easily soluble in water but insoluble in alcohol. It serves as a key precursor in the preparation of tungsten powder, tungstates, and catalysts, and is widely used in electronics, catalysis, and functional materials.

The bulk density of ammonium metatungstate (AMT) refers to the mass per unit volume of AMT powder in its naturally piled state, typically measured in g/cm³ or kg/m³. The term "natural piling" emphasizes that the powder is not compacted by external force but settles freely into a container under gravity, reflecting microstructural features such as porosity between particles, particle shape, particle size distribution, and surface roughness.