Mrs. Johnston heated 5 grams of sugar. The sugar first looked shiny, then melted and became dark brown. Finally, all that was left was a black, shiny substance. She then heated 5 grams of sand in the same way. The sand’s appearance did not change. What explains these results? F Sand is an element, but sugar is a compound. G Heating the sugar caused a chemical change. H Heating the sand caused a chemical change. J Heating the sugar caused it to melt.

The answer is c hope this

stands for electromotive force and it is measured in volts. despite its name, it is not actually the force in the sense of being a "pushing" or "pulling" (not measured in newtons).an equation that relates emf,  ℰ,  to a battery's terminal voltage, v, current, i, and internal resistance, r, is    ℰ = v + irin this case, the emf can be interpreted as a voltage—a difference in electric potential.i would not say that it would be considered an energy. if emf can be defined as the energy/work per a unit charge from a battery or other electric source, then it is not strictly energy.