Another rock is dropped from a higher point and falls for seconds before hitting the ground. assuming acceleration due to gravity ia 9.8/ms2. what is the rocks final velcity the instant before it hits the ground

The amount of heat required to change liquid water to vapor at its boiling temperature is 2256 kj/kg. the amount of heat required to change liquid mercury to its vapor state at its boiling temperature is 295 kj/kg. one kg of each substance is currently at its boiling point. how will the amount of thermal energy required to change each substance from a liquid to a gas differ?