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during a physical science lab investigating chemical reactions, several students placed a 30g antacid tablet in a 30g zip-lock bag. they recorded the masses of the tablet, and the bag. then they added 50 grams of water and quickly sealed the bag. the tablet began to fizz and soon disappeared. the bag was filled with gas. if the mass of the liquid after the reaction is completed is still 50 grams, how much gas is produced? a) 30 grams b) 50 grams c) 80 grams d) 90 grams

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.