Is calcium disodium ionic or covalent?

Acandle’s wick is the fabric string that holds the flame, and it burns down at a constant slow pace when the candle is lit. the wick is usually surrounded by wax. which is the most important property of covalent compounds that makes them useful for making candle wax? a low boiling point a low melting point a high boiling point a high melting point

The ammonia molecule in the diagram has the observed bond orientation because

Which description best characterization the motion of particles in a solid