- a) Exothermic, heat is given off because it burns. b) endothermic, gains heat from body heat to evaporate c) endothermic, gains heat from surrounding.
- Good explosion is a rapid high energy reaction (very exothermic). For this condition to arise, the bond energies of the products have to be larger than those of the reactants. This will lead to a large negative net energy which shows an exothermic reaction.
- Heat is a consequence of motion at the molecular level while temperature is a measure of the average speed of that motion. An everyday example would be the usage of a metal spoon in a hot soup. The heat of the soup gets transferred to the spoon. There’s a difference in temperature between the bowl of the spoon and the handle of the spoon so heat travels from the bowl to the handle. The higher the heat energy, the faster the transfer.
- a) An octane number of 98 means a knocking characteristics of 98% of issoctane and 2% heptane. b)The octane rating shows us nothing about whether the fuel contains oxygenates.
We may not be the brightest but we are the coolest.