What property of sodium chloride makes it useful as a flavouring?
Sodium Chloride is made up of less reactive, sodium and chloride ions. It will hence not harm your body. Since it is an ionic substance, it is fully soluble and therefore digestible. (Basically, if this was a test, you’d have to pull out all the properties of ionic substance.) It has a moderately high melting point, will remain as solids in room temperature and can hence be stored/used easily. Finally, you can talk about the fact that when disolved in water, ions are free to move around to carry charge (if it has anything to with the function of electricity in human body, i don’t know much about biology, so can’t exactly explain that bit haha sorry).