Original Answer:
When we say equilibrium, it is a state of balance. Meaning the summation of all forces in a system is equal to zero and the three states of equilibrium are; stable, unstable and neutral. Equilibrium has many different meanings, depending on what subject (chemistry or physics) or what topic (energy or forces). Dealing with energy there are three types of equilibrium. Stable is when any sort of movement will heighten the object's potential energy. When objects in stable equilibrium are moved, they have a tendency to fall back to their original position. For instance, a skateboarder at the bottom, in the middle, of a ramp. Either way the skateboarder moves, his/her potential energy will increase because he/she will be raising in height. The boarder will also roll back to the bottom of the ramp if he/she doesn't exert any sort of energy to maintain the new position.
Unstable is when any sort of movement will lower the object's potential energy. When such objects are moved, they cannot return to their original position without some exertion of energy. For instance, when a coin is placed on its side, it exhibits unstable equilibrium. Any sort of push will cause the coin to fall flat, lowering its center of mass. The coin will not return to its side unless someone picks it up and resets it. Neutral is when any sort of movement does not affect the object's potential energy. For instance, a ball on a table exhibits neutral equilibrium. If the ball rolls, the center of mass stays at the same height and thus it maintains the same equilibrium.
At equilibrium the concentrations of reactants and productas remain constant.
Reversible reactions are those where the products are in equilibrium at a set of conditions. For one of the most simple examples to illustrate this, look at ice water. At equilibrium conditions, a class of ice water is half ice and half water. If you shift the conditions by heating the ice water, ice will melt to bring the temperature back to equilibrium conditions but the ratio of ice to water will have changed.
D. no movement into or out of the population
The first condition of equilibrium can be applied on concurrent forces that are equal in magnitude, since these produce translational equilibrium. But if the forces are equal in magnitude but are non concurrent then even first condition of equilibrium is satisfied but torque is produced which does not maintain rotational equilibrium. Hence for complete equilibrium that is, both translational and rotational , both the conditions should be satisfied.
temperature, pressure (in the case of gases), concentration
An equilibrium constant
An equilibrium constant
i dont known
Equilibrium means that an object will stay at rest or not accelerate; the conditions are the net force is zero and the net moment about any point is zero.
At equilibrium the concentrations of reactants and productas remain constant.
At equilibrium the concentrations of reactants and productas remain constant.
It is in equilibrium when the two conditions are satisfied - there is no net translational equilibrium and no net rotational equilibrium. For translational equilibrium, the summation of forces acting on the matter must equate to zero, which means that there is no resultant force. For rotational equilibrium, the sum of moments must be zero, which means there is no resultant torque. When these two conditions are met, the object will be stationary, i.e. it is in a state of equilibrium.
Mutation cannot occur
Reversible reactions are those where the products are in equilibrium at a set of conditions. For one of the most simple examples to illustrate this, look at ice water. At equilibrium conditions, a class of ice water is half ice and half water. If you shift the conditions by heating the ice water, ice will melt to bring the temperature back to equilibrium conditions but the ratio of ice to water will have changed.
Mutation cannot occur
The Chatelier's Principle states that when a dynamic equilibrium is disturbed by changing conditions then the position of equilibrium shifts to counteract the change to reestablish equilibrium. A chemical reaction is at equilibrium and experiences a change in pressure, temperature, or concentration of products , equilibrium will shift in opposite directions to offset change.
D. no movement into or out of the population