If a 72-candela light source is located at a distance of 3 meters from a surface, the illuminance on the surface is lux. a. 648 b. 24 c. 8 d. 216

Which statement is true about ionic compounds?

Write the empirical chemical formula of calcium with a mass percent of 38.8, phosphorus with a mass percent of 20.0, and oxygen with a mass percent of 41.3.

If a polyatomic ionic compound has gained two hydrogen ions, then how does its name begin?