Heat Changes Associated with Chemical Reactions, Hess’ Law, and Reaction Profiles

On a package of military MRE’s (Meal, Ready to Eat) you can find the following statement:

Restriction of food and nutrients leads to rapid weight loss, which leads to: loss of strength, decreased endurance, loss of motivation, and decreased mental alertness.

As you know, food is very important. Soldiers are not the only ones in need of a quick meal. Areas stricken by war and natural disasters also find themselves in need of aid. How do MRE’s work? The image above shows a soldier in Iraq handing a six-year-old girl an MRE. What will she need to do to prepare the meal? Would you want to eat cold spaghetti?

All MRE’s come packaged with a flame-less heater. This heater is used to heat portions of the meal. The flame-less heater uses a simple chemical reaction to provide sufficient heat to warm the food. Also, in case you are wondering, MRE’s come in twenty-four varieties or flavors. This is all possible due to the study of heat transfer. Listed below are a few flavor examples:

• Spaghetti with Meat Sauce
• Beef Stew
• Black Bean and Rice Burrito
• Cheese Tortellini
• Pork Rib and Clam Chowder