Ethyl alcohol has a heat of vaporization of 850. j/g. what mass of ethyl alcohol can be boiled using 15000 j of energy?

The amount of heat, H, needed to boil off certain mass, m, of the substance is given by the equation,
                                H = mHv
where Hv is the heat of vaporization. Manipulating the equation, the mass is calculated by,
                                m = H/Hv
Substituting the known values,
                                m = 15000 J/(850 J/g) = 17.65 g
Thus, the mass of ethyl alcohol is approximately 17.65 g. 

Yes, endothermic means it turns cold. and some chemical changes include change of tempature.