Consider the following system at equilibrium:
D(aq)+E(aq)<=>F(aq)
Classify each of the following actions by whether it causes a leftward shift, a rightward shift, or no shift in the direction of the net reaction.
Increase D
Increase E
Increase F
Decrease D
Decrease E
Decrease F
Triple D and reduce E to one third
Triple both E and F

Increase D  ⇒ rightward shift

Increase E  ⇒ rightward shift

Increase F  ⇒ leftward shift

Decrease D  ⇒ leftward shift

Decrease E  ⇒ leftward shift

Decrease F ⇒ rightward shift

Triple D and reduce E to one third  ⇒ no shift

Triple both E and F ⇒ no shift

Explanation:

Changes in the concentrations of reactants y products affect to the equilibrium. In this case, D and E are reactants and F is the product.

When a change in the factors affecting equilibrium occur, the system will react in order to counteract the change imposed.

If a increase of reactant occur, the system will tend to produce more products (rightward shift). For example: increase D, increase E. In contraposition, if a decrease of reactant occur, the system will produce more reactants (leftward shift). For example: decrease D, decrease E.If a increase of product occur, the system will tend to produce more reactants (leftward shift). For example: increase F. In contraposition, if a decrease of product occur, the system will produce more products (rightward shift). For example: decrease F.If we change both reactants and products concentration in the same amount, the net change is zero, so there is not shift. For example: Triple D and reduce E to one third (D x 3 and E/3, there is not change in the total amount of reactants) ; Triple both E and F (E x 3 and F x 3, the net change is zero).

The independent variable is the type of music.the dependent variable is the pulse rate.the intervening variable is the age of the subject.if the mother does not like rock, her pulse is likely to not increase.the same might be true for the sister.the friend may like rap and gets excited.to establish cause/effect relationship, all of the subjects must be consistent.hope i .