Initial Rates = Maximum rates [ENDORSED]

[Hasmik Dis 2F]

In his lecture, Lavelle was saying how the initial rates are the maximum rates. Can anyone explain what he means by this and why is it relevant?

[Rachel Jiang 3H]

The initial rates are the maximum rates because reaction rate depends on the concentration of the reactant. At the start of the reaction, the reactant concentration is the highest, therefore leading to the highest reaction rate. We only want to study the initial rate because there are little product present at that time so we do not need to take into account the reverse reaction. Hope this helps!

[Jenny Lee 2L]

Hello! I wanted to add that the initial rates are maximum rates also because initially, reactants are solely forming products. However, as time passes, there is a forward and reverse reaction happening because some reactants are forming products while some products are going back to form reactants. Therefore when there are little to no products, then only the forward rxn is happening, and thus the initial rate is the maximum rate at which the reaction proceeds forward.

[Lauren Sarigumba 1K]

The initial rate is the maximum rate because that is when there is little product, and since the reaction is trying to reach equilibrium, the rate at which the initial concentration of reactant that turns into the product will be the fastest, and thus maximum, rate.

[Dominic Benna 2E]

Rates are dependent on the amount of reactant. As a reaction goes forward, the amount of reactant falls as it becomes product, and thus the rate of the reaction changes as there are less reactants and products start to form reactants in the reverse direction. By taking the initial values, or the maximum values, of reactants, we will get the maximum rate as we have purely reactants forming products with the greatest value of reactants.

[Inderpal Singh 2L]

The rate depends on the amount of reactant. When we take the initial value, we do not let the reactant decrease, therefore, we will get the maximum rate.

[kateraelDis1L]

I remember it as the idea that we study initial rates because at the beginning of the reactions products are being produced faster than towards the end when the reaction is reaching equilibrium. This slowing down can mess with our rate numbers so we study initial (aka where the rate are at maximum) only.

[Isabel_Eslabon_2G]

I think the initial rate is considered the maximum rate because there is the most reactant available. Once the reaction starts occurring, the amount of reactant decreases. During the initial rate, there is very little product formed, so the reverse reaction is considered to not be taking place (of course, experimentally you'd want to have those products removed anyway).

[Chem_Mod]

Good answers. Good Chemistry. :-)

[Hasmik Dis 2F]

Thanks everyone:))