Chemistry - Reaction rates

[40f0b2c8357d4547aeb44fc3bb0e2945]

Hi!
I'm actually doing an experimental science assignment and I had some questions regarding reaction rates.

My experiment's aim is to investigate whether the increased quantity of Sodium Chloride (table salt) impacts the duration of the reaction when added to oil and water.
With the oil water ratio as 1:3, I am adding different quantities of salt to determine if more salt impacts the duration of the reaction.

So my question is, as I increase the salt, the reaction rate increases due to the collision theory, however, I am finding it difficult to explain how the actual DURATION of the reaction (in seconds) increases.
A higher reaction rate means the experiment lasts longer due to successful reactant collisions? Is this scientifically valid? I browsed the internet for a prolonged time but I couldn't get a direct answer.

Please help! Thank you!!

Syna

[norman40]

Hi Syna,

A reaction is over when the amounts of reactants and products are no longer changing. This is the point at which equilibrium is reached.

If you increase the rate of a reaction but the equilibrium point is the same, then the duration of the reaction is reduced. An increased rate could produce a longer duration if the equilibrium shifted toward product formation.

Shifts in the equilibrium point result from adding reactants, removing products or increasing the temperature. One of these factors may explain your results.

That said, I'm not clear on the reaction you are studying. Some additional details about the reactants, concentrations and experimental conditions would be useful for answering any other questions you may have.

I hope this helps. Please ask again if you have more questions.

A. Norman

[40f0b2c8357d4547aeb44fc3bb0e2945]

Hi A.Norman,

Thank you so much for the reply. It significantly helped my research.
I was further confused on how to express this reaction through a chemical formula/equation, as I cannot find a definite solution.

(For additional details about the experiment, I am studying the chemical reaction of salt quantity on oil and water. With Canola oil layered on top of the water in a ratio of 1:3 in a cylindrical glass. (60ml of canola oil and 180ml of water) The salt is poured in ascending 1/2 teaspoon quantities to measure the duration of the resultant reaction. The reaction forms because salt is heavier than water, so when you pour salt on the oil, it sinks to the bottom of the mixture, carrying a blob of oil with it. As it dissolves, the salt releases the oil, which floats back up to the top of the water, stimulating bubbles)
Independent variable : quantities of salt
Dependent variable : Duration of reaction

[norman40]

Hi Syna,

Thanks for posting additional information about your experiment.

In a chemical reaction one or more reactants are converted to different substances (or products). For a more detailed definition see: https://www.britannica.com/science/chemical-reaction

No reactants are converted to products in your experiment so it is not a chemical reaction. And you will not be able to express the process you described in a reaction equation. You might try expressing your experiment as a process with a series of steps (oil layer on water, add salt, etc).

I think the duration (how long it takes for the salt to release the oil) depends on how long it takes for enough salt to dissolve to allow the oil “glob” to float again. So factors that change how fast the salt will dissolve will alter the duration.

I hope this helps. Please ask again if you have more questions.

A. Norman