The meals-ready to eat (MRE) in the military can be heated on a flameless heater. Assume the reaction in the heater is:
Mg(solid) + 2H2O(liquid) ----> Mg(OH)2(solid) + H2(gas)
Calculate the enthalpy change under standard conditions (in joules) for this reaction. What quantity of magnesium is needed to supply the heat required to warm 25mL of water (d=1.00g/mL) from 25 to 85 degrees Celsius?