what does MRE stand for
Meals Ready to Eat
Define the word "EXOTHERMIC"
According to our energy models, a system of reactions that heats up is called...
a heater system
reaction system
When you combine 2 Hydrogen (H) atoms with an Oxygen (O) atom, what do you create?
H20
Water
"Property"
a characteristic of a substance (color, density, odor, flammability, solubility, etc)
what 3 substances were used to cause a reaction in the MRE heater?
copper sulfate (root killer)
aluminum foil
saltwater
Define the word "ENDOTHERMIC"
a reaction that absorbs heat, makes the surroundings colder
According to our energy models, a system that absorbs heat is called...
the food system
absorbing system
What is the common name for CuSO4?
Copper Sulfate or root killer
"Criteria"
something that describes what the "must-haves" or "goals" of a solution are
what kind of liquid MUST be used to start the reaction in a homemade MRE heater?
saltwater
burning wood
Exothermic
What happens to the particles in the heater (reactants) as they combine
they move faster
What kind of reaction can CREATE a new substance?
a chemical reaction
limitations to a solution
What temperature is considered TOO HOT for most people to eat food at?
45 degree Celsius
113 degrees Fahrenheit
ice melting
endothermic
Heat is transferred from the heater to the food system by_____ (conduction, convection, or radiation)
conduction (touching)
If heat is produced or a gas is released during a reaction, this is known as...
a chemical reaction
"Prototype"
an early-stage design or solution to a problem
What ratio of REACTANTS to FOOD do you think is always going to be too hot in an MRE lab test?
200:200
180:220
bread baking
endothermic-- the bread (dough) is absorbing the heat as it bakes, making the surrounding area feel colder than the bread
if you want to reduce the temperature during a thermal (heat) reaction, you can...
use less reactants
wait longer for the system to cool down
open the system to let heat escape
Describe what happens to particles when chemical combine and form a new substance.
(Like if a liquid and solid combine and it makes a new gas)
The particles break apart from their original form and reconnect in a new way, which makes that new substance.
"Insulate"
reduce the amount of heat lost, keeps heat in, does not transfer heat energy well