Which nuclear emission has no charge and no mass

Astudent reacts 13 moles of iron with 21 moles of oxygen according to the following equation:

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

How is the way a mixture is combined different from how a compound is combined?