The meals-ready-to-eat (MREs) in the military can be heated on a flameless heater. You can purchase a similar product called “Heater Meals.” Just pour water into the heater unit, wait a few minutes, and you have a hot meal. The source of energy in the heater is 

Calculate the enthalpy change under standard conditions, in joules, for this reaction. What quantity of magnesium is needed to supply the energy required to warm 25 mL of water (d = 1.00 g/mL) from 25°C to 85°C?

Transcribed Image Text:

Mg(s) + 2 H₂O(l) → Mg(OH)₂(s) + H₂(g)