Given the EÂ° values for two half reactions, you can easily predict the potential difference of the corresponding cell: simply add the reduction potential of the reduction half-cell to the negative of the reduction potential (that is, to the oxidation potential) of the oxidation reaction.
How to Melt Glass With a Torch. Glass melting has a long history, going back to approximately 3000 BC. In these early times, glass was melted to decorate vases. Glass is made up of silica, sodium carbonate and calcium carbonate. Most glass melts at 1400 to 1600 degrees Farenheit. Nevertheless, there are specialized glasses that will melt at as low as 900 degrees.
This is related to the glass transition temperature, which is the temperature where an amorphous solid becomes soft near its melting point or a liquid becomes brittle near its freezing point. Most glass you encounter is silicate glass, which consists mainly of silica or silicon dioxide, SiO 2. This is the type of glass you find in windows and drinking glasses. The crystalline form of this mineral is quartz. When the solid material is non-crystalline, it is a glass. You can make glass by melting silica-based sand. Natural forms of silicate glass also exist. Impurities or additional elements and compounds added to the silicate change the color and other properties of the glass.