Final answer:
In a solution with a concentration of 55.5 M H₂O, the equilibrium is likely to favor hydrolysis rather than peptide bond formation, due to the abundance of the product water, which pushes the equilibrium towards reactants.
Step-by-step explanation:
When considering whether the equilibrium of a reaction will lie in the direction of peptide bond formation or hydrolysis in a solution of 55.5 M H₂O, one must take into account the principles of chemical equilibrium, specifically Le Chatelier's principle, which indicates how equilibria shift in response to changes in concentration. In a dehydration synthesis reaction, such as peptide bond formation where a molecule of water is released, if the water concentration is very high, the equilibrium could be driven towards the reactants, favoring hydrolysis instead of peptide bond formation. This is because adding more of a product (water, in this case) will shift the equilibrium to the left, towards the reactants, to reduce the stress of the increased product concentration, according to Le Chatelier's principle.
Therefore, in a solution with a high concentration of water (55.5 M), the equilibrium would likely favor the hydrolysis of the peptide bond rather than its formation because there is an abundance of the product of the peptide bond formation reaction, which is water. The existing high concentration of water will push the reaction in the direction where water acts as a reactant, which is hydrolysis, breaking the peptide bond and forming the individual amino acids.