Kinetics
The "energy hurdle" that must be overcome for a collision to result in a reaction.
Activation Energy (Ea)
The pressure exerted by a gas that is in a state of balance with its liquid phase in a closed container.
vapor pressure
This property explains why adding salt to water allows it to cook pasta at a temperature higher than 100°C
Boiling Point Elevation
Define molarity. Be specific.
This unit is defined as moles of solute per Liter of total solution (M solute/L solution)
In the rate law Rate = k[A][B], this is the overall order of the reaction.
Second Order (1+1=2)
This substance increases the rate of a reaction without being consumed by providing a lower energy pathway.
catalyst
This condition is reached when the rates of forward and reverse reaction equal each other.
equilibrium
This represents the number of particles a solute breaks into when dissolved in a solvent.
Van't Hoff Factor (i)
Define molality. Be specific.
This unit is defined as moles of solute per kilogram of solvent.
These are the units of the rate constant (k) for a zero-order reaction.
M/s (or mol/L·s)
The [BLANK] in a multi-step reaction mechanism that limits how fast the overall reaction can go.
Rate-Determining Step (RDS)
As the strength of intermolecular forces (IMFs) in a liquid increases, this happens to its vapor pressure.
decreases
What is the Van't Hoff factor (i) for a molecule of Glucose (C6H12O6)?
i = 1
This unit is preferred when studying properties that change with temperature because mass does not expand or contract.
molality
Doubling the concentration of reactant [A] causes the rate to quadruple. This is the order of the reaction with respect to A.
second order
If a reaction is first-order, this value remains constant regardless of the starting concentration. (look at exam information sheet).
In a mixture of gases, the total pressure is the sum of these individual pressures for each gas present.
partial pressure
Adding a non-volatile solute to a solvent causes the vapor pressure of the solvent to do this.
decrease
To calculate a mole fraction, you divide the moles of one component by this value.
Total moles of all components
A reaction is first-order with k = 0.020 min⁻¹. If the initial concentration is 0.80 M, what is the rate of the reaction?
0.016 M/min (Rate = 0.020 * 0.80)
A reaction has a rate law of Rate = k[A]^2. If the concentration of A is doubled, the rate increases by this factor.
4
A gas mixture has a total pressure of 12 atm and contains 3 moles of He and 1 mole of Xe. What is the pressure of He?
9 atm (Partial Pressure)
You have 1.0 m NaCl and 1.0 m CaCl2. Which solution will have the lower freezing point?
1.0 m CaCl2 (i=3 vs i=2)
If you dissolve 0.5 moles of sugar in 500 grams of water, what is the molality of the solution?
1.0 m
This is the only factor that can change the value of the rate constant (k) for a specific reaction.
temperature