Measuring how fast a reaction occurs. Someone has to do it, right?
1) The study of reaction rates, and 2) the cause of many sleepless nights for chemistry students worldwide.
Just like reaction kinetics, too. Favored by lazy people who don't want to write an extra work.
If you ask us, equilibrium should've been spelled EQUALibrium. In equilibrium, every force that acts on an object is canceled out. An object in equilibrium will either stand still or move at constant speed (without acceleration) unless a force changes and puts it out of equilibrium, causing acceleration.
A theory (duh) that says reactants need to do two things for a reaction to occur: slam into one another with sufficient force, and do so at the right angle.
The amount of energy that is needed to kick off a chemical reaction and get the party started.
Reactions go through a path where they become less like reactants and more like products. Like adolescence for molecules.
An unstable, intermediate substance that forms as reactants transition into products in a chemical reaction. Sort of like the teenage years of a famous child actor.
A particularly handy molecule that speeds up the rate of a reaction by helping reactants make successful collisions. We call it the Cupid of the chemical reaction world. Ain't love grand?
The rate at which reactants change into products. In other words, how fast a reaction happens.
Yep, a lot of laws in thermodynamics. This one is a mathematical representation of the rate of a specific reaction.
A value used in the calculation of a reaction rate. This value is always the same (surprise surprise) for a given reaction performed under the same conditions.
Those crazy exponents above the concentrations in a rate law.
Sum of reaction orders of all reactants.
The time required for a radioactive isotope to decay by half in number. If you have 100% carbon-14 in a substance, the half-life would be the time to 50% carbon-14.
Equation that relates the rate constant k to activation energy.
Constant in Arrhenius equation, which describes how often molecules collide the "proper" way for a reaction to occur. Proper collisions sound very British, but frequency factors can be found anywhere.
Equilibrium where individuals may be changing, but the system as a whole is not changing.
Represented by the symbol Keq, a numerical value that describes the ratio of products to reactants at equilibrium. Keq > 1 mean that the reaction is mostly products, so the forward reaction is favored. Keq < 1 mean that the reverse reaction is favored, because the reaction is mostly reactants.
A disturbance to an equilibrium system is resisted by the system.
The study of the movement of heat.
This law states that energy is conserved in a closed system. The change in the internal energy, ΔU, of a system relates to energy, Q, in the form of heat, added to the system, and in the form of mechanical work, W, that leaves, or is done by the system. Want an equation? Here's an equation: ΔU = Q − W. Here are some important sign conventions to remember:
This law says that heat will always flow from warm to cold in a spontaneous process. Another way of putting it is that the entropy of a system can only increase or stay the same. Even though energy is conserved, we can never turn all of the available heat energy into mechanical work. Just like we can never turn back the clock. Well, as long as the clock is a metaphor for the passage of time, rather than an actual clock.
Perfect crystal + absolute zero Kelvin = zero entropy
The internal energy of a system is the average energy of all of the molecules in that system. A warm object has high internal energy—its molecules zip about like there's no tomorrow. A cold object has slow-moving molecules, because of its low internal energy.
A means by which energy is transferred from a hot body to a colder body when the two are placed in thermal contact with one another.
In physics, mechanical work is done any time a force moves an object—and lucky for us, the forces' union hasn't really negotiated a minimum wage yet, so we can get forces to do work all the time for pretty much free. Whenever a force F displaces an object a distance d, the work done is found by W = Fd. The unit of work is then a newton-meter, which works out to be exactly the same as a joule—the unit of energy.
The change in the thermal energy of a system, also known as the heat of reaction. On the streets it goes by the symbol ΔH.
A measurable quantity, often noted as ΔS for kicks, that represents the disorder in a system or surroundings. More technically, knowing the entropy of a system can help us determine the energy available for work in a process. That's right, Nature makes all of her randomness available for good use.
Thermodynamics version of a thumbs up or thumbs down for whether a reaction occurs naturally.
Act of being fanciful, willing to make a sudden change
A process that absorbs heat.
Exothermic is the term used to describe a reaction that releases heat.
This is our standard unit for measuring energy, not to be confused with the rock we're rocking.