5E Equilibrium in reversible reactions-Law of Mass Actions

The reversible reaction

Hb+4O₂⇄Hb(O₂)₄

exists in blood between hemoglobin (Hb) and oxyhemoglobin Hb(O₂)₄.

According to the law of mass action, doubling the O₂ concentration would:

• decrease the reaction quotient by a factor of 16.

• 1) The law of mass action- reaction quotient Q is the ratio of the molar concentrations of the products/ reactants each praised to their coefficients

• 2) If [O₂] is initially = x mol/L and is then doubled to 2x mol/L, the change will be raised to the power of 4 = ([2x]⁴ =16x⁴).

• 3) Because [O₂] is in the denominator of the Q expression, this will decrease the value of the reaction quotient by a factor of 16 relative to the initial value of Q.

Reactions tend to proceed toward equilibrium by shifting species concentrations until Q equals the equilibrium constant Keq.

• True

• False

Q indicates the (a)   a reaction must shift to reach equilibrium.

Keq is (a)   for a reaction at a given temperature.

When Q<Keq the reaction shifts

• to the right

• to the left

When Q>Keq the reaction shifts

• to the right

• to the left

Which law states that if the system is at equilibrium at a given temperature, then the following ratio is a constant:

(a)  

If the system is NOT at equilibrium, the ratio is different from the equilibrium constant. The ratio is called a reaction quotient which is designated as Q.

• True

• False

Solids and liquids are included in equilibrium expressions?

• True

• False