Which one among the following statements is not true for glass?

Statement 3 is incorrect because glass is an amorphous solid, not a crystalline one. Glass formation occurs when a liquid is cooled rapidly enough to prevent crystalline nucleation and ordering [1]. This rapid cooling circumvents the crystallization process, resulting in a disordered, metastable state known as a supercooled liquid. If slow cooling were to occur, the material might develop crystallinity, but the resulting substance would no longer be classified as glass. Regarding the other options: sodium silicate is indeed commonly known as water glass due to its water solubility [2]. Glass is scientifically described as a supercooled liquid because it retains a liquid-like disordered structure while possessing the mechanical rigidity of a solid [1]. Finally, colored glasses are produced by adding various metal oxides or coloring materials during the melting process [3].

Sources

1. [1] https://pmc.ncbi.nlm.nih.gov/articles/PMC11725876/
2. [2] https://www.osti.gov/servlets/purl/1767764
3. [3] https://en.wikipedia.org/wiki/Glass