Question

what is constant about the equilibrium constant?
A. ratio of products to reactants at equilibrium is constant
B. concentrations of products present at equilibrium are constant
C. concentration of reactants present at equilibrium are constant
D. reversibility of the reaction at equilibrium is constant

Answer 1

okay let me explain this to you

Answer 2

take it away

Answer 3

In our reaction we have our reactants that become products rights.

\[A + B --> C + D \]

A and B are our reactants and C and D are our products

Answer 4

Yeah

Answer 5

now, at a certain temperature, equilibrium will be established. this means that

we have reactants going to products and products going to reactants. so at a certain point the rate of the forward reaction is equal to the rate of the reverse reaction and at this point we have equilibrium reached.

when we take the ratio of concentrations of products to reactants at equilibrium we get a number called the equilibrium constant.

\[k_{equilibrium~constant} = \frac{ products }{ reactants } = \frac{ [C][D] }{ [A][B] }\]

where [ ] means concentration.

Answer 6

so the concentrations should be equal then

Answer 7

not necessarily

Answer 8

@fifib the rates of the forward reaction and reverse reactions are equal but that doesn't mean that the concentrations of reactants and products are the same.

think about it this way.

if we have 3 molecules of product and 2 molecules of reactant.

at equilibrium for example. one molecule of reactant is becoming product and one molecule of product is becoming a reactant.

the concentration of reactants and products aren't necessarily the same at equilibrium.