Equilibrium
In a chemical equation at equilibrium, what can be said about the rate of the forward and reverse reactions?
The forward rate is higher.
The reverse rate is higher.
Both rates are zero.
They are equal.
If Q < K at a certain moment during a chemical reaction, what will happen as the system approaches equilibrium?
The reaction will proceed in both directions at the same rate
The reaction will proceed in the reverse direction
The reaction will proceed in the forward direction
It will not change
In which scenario would increasing temperature most likely cause a reaction to shift from spontaneous to non-spontaneous?
An endothermic reaction with no significant change in order or disorder.
An exothermic reaction with an increase in order (decrease in entropy).
An endothermic reaction with an increase in disorder (increase in entropy).
An exothermic reaction accompanied by an explosion which increases disorder dramatically.
What type of chemical equilibrium involves charged species?
Gravitational equilibrium
Nuclear equilibrium
Covalent equilibrium
Ionic equilibrium.
A solution contains 10 molecules of X and 20 molecules of Y at Time t=0. At Time t=10sec, there are 5 molecules of X and 25 molecules of Y. Is this reaction possible?
No: equilibrium means that the number of molecules of product and reactant must be the same.
Yes: equilibrium means that the rates of reaction are equal, not that the product and reactants are equal.
Yes: the temperature could be very low so as to cause a reverse reaction.
There is not enough information to determine this without the molarity of molecule X and Y.
What will be the result if solid sodium chloride is added into a saturated solution that is at dynamic equilibrium with undissolved NaCl?
Sodium ion concentrations rise, promoting precipitation until new salt dissolves completely restoring initial conditions.
Chloride ion levels decrease as additional NaCl promotes further dissolution compensating for introduced solids.
Dynamic equilibrium temporarily disrupts before reestablishing itself accommodating extra sodium chloride via increased dissolution.
No change occurs since solid sodium chloride addition doesn't alter saturation levels or ion concentrations.
What effect does adding more solute have on a saturated salt solution at equilibrium?
The excess solute immediately dissolves increasing the concentration.
The original amount of dissolved salt precipitates out entirely.
The salt remains undissolved until some solvent evaporates or salt precipitates.
No change occurs; the added solute dissolves maintaining saturation level.

How are we doing?
Give us your feedback and let us know how we can improve
Given a particulate diagram, how can you identify which way the reaction has shifted?
Look at the number of reactants on each side.
Look at the ratio of certain products and reactants in the chemical equation.
All of the above.
Look at the number of products on each side.
Which property is most likely affected by the polarity of a molecule?
Density
Molecular mass
Melting point
Solubility in water
When investigating homogenous aqueous acid-base equilibrium mechanisms, what question best probes how conjugate base strength influences acid dissociation constants (Ka)?
How much do thermodynamic properties impact acid dissociation constants when discussing nonstandard state reactions at variable temperatures?
Can the inclusion of common ions in the Henderson-Hasselbalch equation significantly modify Ka calculations for buffers?
Does the presence of strong electrolytes in solution alter Ka values for weak acids under constant pH conditions?
What is the relationship between conjugate base strength and acid dissociation constants for weak monoprotic acids?