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Rate of Reactions
The rate of reaction refers to how quickly a chemical reaction proceeds and it is important because it determines the efficiency and safety of chemical processes in various industries. The rate of reaction can be measured in two primary ways:

1. tracking the increase in amount of product produced per unit time
   e.g. measure the amount of gas produced every 5 minutes
2. measuring the decrease in mass of the reactants within a vessel per unit time
   e.g. measure the mass of the conical flask that the reaction is taking place in every 5 minutes

You can alter the rate of the chemical reaction by modifying any of these five rate of reaction factors: concentration, pressure, particle size, temperature and presence of catalyst.

Changing the rate of a chemical reaction affects how quickly the reaction reaches completion (the rate), but it does not alter the amount of product formed at the end (the yield). Imagine this: both you and a friend are both running 2.4km. You might run faster, finishing the race in a shorter amount of time, while your friend takes a slower pace, finishing later. Despite the difference in speed, both of you cover the same distance of 2.4km. Similarly, in chemical reactions, speeding up or slowing down the reaction rate through various factors like temperature or catalysts doesn’t change the total amount of product produced.

Rate of Reaction graphs
This rate of reactions chapter is one that is packed with graphs and tables, making it rich in visual data representation. Let’s start with graphs.

Following the two ways that can be used to measure the rate of reaction (see above), there are two types of graphs to visualise these measurements:

1. An ascending graph, where the amount of product produced is plotted against time (which is increasing)
2. A descending graph, where the mass of the reactant or vessel is plotted against time (which is decreasing)

The table below shows the general setup and illustrative graphs for both methods of measuring the rate of reaction. I have highlighted the essential features of the graph below it, with the most critical aspect being the gradient of the graph as it shows us the rate of reaction.

Measuring the increasing volume of product (gas) formed over time

This rate of reaction graph measures the volume of gas produced over time, which is generally increasing. The gradient of the graph shows us the rate of reaction, which is steepest in the beginning, gentler in the as the reaction progresses, and zero at the end.

The gradient of the graph is the steepest in the beginning, as the rate of reaction is the fastest when the concentration of reactants is the highest.

As the reaction progresses, the gradient of the graph becomes gentler, indicating a slowdown in the rate of reaction due to the decrease in concentration of reactants.

Finally, the gradient reaches zero as the reaction comes to a stop, signifying that all the reactants have been consumed.

Measuring the decreasing mass of reactant/vessel over time

This rate of reaction graph measures the mass of reactants over time, which is generally decreasing. The gradient of the graph indicates the rate of reaction, starting out steepest in the beginning, becoming gentler as the reaction proceeds, and eventually reaching zero.

The gradient of the graph is the steepest in the beginning, as the rate of reaction is the fastest when the concentration of reactants is the highest.

As the reaction progresses, the gradient of the graph becomes gentler, indicating a slowdown in the rate of reaction due to the decrease in concentration of reactants.

Finally, the gradient reaches zero as the reaction comes to a stop, signifying that all the reactants have been consumed.