Annealing of this material is accomplished in lehrs. An industrial method to produce a type of this material lays liquid raw materials over tin to form a float. Diffusion of interfering ions described by the Nikolsky–Eisenman equation across this material is seen in electrodes, which can be used to measure pH. (10[1])Sintering (10[1])particles of this material into hollow disks creates fritted examples of these materials that are used as filters. Addition of boron trioxide lowers the coefficient (10[1])of thermal expansion of these materials. Silica, soda ash, and limestone produce the molten form of this material, (10[1])which is then solidified by blowing. (10[1])For 10 points, (10[1])what amorphous material is often used to make lab materials and window panes? ■END■