Charlie McEvoy Jr., age 14, of Fredericton, N.B., Canada, for his question:

WHAT IS TITANIUM?

Titanium is a silver gray, lightweight metal. Its density lies between that of stainless steel and aluminum. It will melt at 9,675 degrees centigrade.

The metal resists sea water and sea air corrosion or rust as well as platinum and better than stainless steel. It also has a higher strength weight ratio than steel.

The first commercial use of titanium was as an oxide to substitute for white lead in paint. Titanium dioxide is also used in the manufacture of linoleum, rubber, textiles, paper, porcelain enamels and welding rods. A compound of barium and titanium can be used in place of crystals in television and radar sets, microphones and phonographs.

Large amounts of titanium are used in aircraft and jet engines because it is strong and light.