A beaker filled with 2182.5 g of water at a temp of 10.0 degrees Celsius is placed over a lamp burning ethanol. What mass of ethanol needs to be burned in order to bring the water to boiling?
First you must determine how much heat must be added to the water to bring it to a boil.
q1 = heat that must be added to move the temperature from 10 degrees C to 100.
q1 = massH2O x specific heat water x (Tf-Ti) where Tf is the final T (100 C) and Ti is the initial T(10 C).
Now look up the heat produced by burning ethanol and calculate the grams of ethanol needed to produce q1. To boil the water, you must add 1 joule more.