Which of the following is a mixture? steel water oxygen gold

Silica, sio2, is formed on silicon as an electrically insulating layer for microelectronic devices. silica is formed when silicon is exposed to o2 gas at an elevated temperature. at 900˚c, it takes 90 minutes for the oxygen to diffuse from the surface to form a 0.06 micron (0.06 x 10-6 m) thick layer of sio2 on

Now consider the reaction when 45.0 g naoh have been added. what amount of naoh is this, and what amount of fecl3 can be consumed by it?

Particle model to predict what will happen if a sharp object creates a hole in the soccer ball