To determine if the compound is an ionic compound, heat it up until the compound reaches its melting point and become molten. Use the molten form to set up an electric circuit and see if the compound will conduct electricity. If the compound conduct electricity then it is an ionic compound. If it does not conduct electricity, it is not an ionic compound. Ionic compounds usually conduct electricity in their molten forms.<span />
There really isn't a difference if you think about it
The reaction of hydrochloric acid and sodium hydroxide is a neutralization reaction wherein a mixture of acid and base produces salt, water, and energy in the form of heat. A neutralization reaction is exothermic, thus producing heat. This is why the beaker felt warm to the touch.