Thermochemical Reactions Flashcards
Spontaneous Reaction
A reaction that will proceed without any outside energy.
Most spontaneous chemical reactions are exothermic - they release heat and warm up their surroundings: for example: burning wood, fireworks, and alkali metals added to water.
Thermochemical Equation
An equation that includes the quantity of energy released or absorbed as heat during the reaction as written.
Energy Profile Diagram
A diagram that shows the energy changes during the course of a reaction.
Exothermic Reactions
Chemical reactions that release a significant amount of heat to the surroundings.
Combustion Reaction
A chemical reaction that occurs when a substance reacts with oxygen, releasing energy in the form of heat and light.
Incomplete Combustion Reaction
Combustion in which not enough oxygen is supplied to completely burn the fuel. Carbon monoxide is a common product.
Exothermic
Energy of the reactants > energy of the products.
Endothermic Reaction
A reaction that ABSORBS energy in the form of heat.
Endothermic
Energy of the reactants < energy of the products.
Heat
The energy transferred between objects that are at different temperatures.
Chemical Potential Energy
The energy stored in the chemical bonds of a substance.
Enthalpy Change
The amount of energy absorbed by a system as heat during a process at constant pressure.
Enthalpy (H)
Total energy of a system.
Enthalpy Diagram
A graphic depiction of the enthalpy change of a system.
Kinetic Energy
The energy an object has due to its motion.
Temperature
A measure of how hot (or cold) something is; specifically, a measure of the average kinetic energy of the particles in an object.
Celsius
The temperature scale on which water freezes at 0 degrees and boils at 100 degrees.
Kelvin
SI unit for temperature (K).
What is the Celsius to Kelvin conversion?
K = C + 273.15
What does the graph appear as for an
Endothermic enthalpy change?
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What does the graph appear as for an
Exoothermic enthalpy change?
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Specific Heat Capacity
The energy required to raise the temperature of one gram of a substance by one degree Celsius.
Carbon Sequestration
The act of removing carbon from the atmosphere and storing it. Plants sequester, or store carbon from the atmosphere.
Carbon Lock
Hydrosphere, biosphere and geosphere oil and gas and coal deposits.
Anthropogenic Climate Change
Climate change which is human caused, either directly or indirectly.
Biofuel
A fuel derived directly from living matter.
Fuel Blends
Blending amounts of alternative fuel with conventional fuel is one way to displace petroleum.
