What is a potential benefit of fuel cell cars?
increased efficiency converting gasoline to energy
no recharging necessary
decreased automobile cost
larger engines

I think the correct answer would be the first option.  potential benefit of fuel cell cars would be an increased efficiency converting gasoline to energy. Fuel cells are found to be about 55 to 60% efficient as compared to combustion engines which is roughly 40%, given that the engine is at its best condition. However, at normal conditions, combustion engines only has an efficiency  of about 25% to 30% which is very far from the 60% of fuel cells.  So, using fuel cells would be much more efficient in converting the fuel into energy and is a good alternative for cars and other fuel using devices.

Answer : option c) heat is released during the process.explanation :

the enthalpy of formation of water is given as -285.8kj/mol, which states that the enthalpy of formation is negative.

negative enthalpy of formation indicates that the heat is released during the reaction process. the heat is released from reaction to the surroundings the enthalpy is expressed with a negative sign with the energy given out in the reaction process.

the formation of water takes place by giving out heat which is -285.8 kj/mol.

Aphysical change is one that you can put in and remove like a ham sandwich. the stuff you put in there can be changem its not permanet. a chemical change is on that can't be change thats permanet. like when you make a cake and bake it. you can't get those ingredients back.