A mole is a unit we use in chemistry to count a large number of particles, like atoms or molecules, in a substance. It's similar to how we use "dozen" to count 12 things, but a mole counts a much larger number—about 6.02 × 10²³ particles!

$Mean rate of reaction =$ $\frac{Amount of Reactant Used (in moles)}{Time Taken}$

$Mean Rate of Reaction= \frac{Amount of Product Formed (in moles}{Time Taken}$

Why Use Moles? Using moles is helpful when you want to think about the number of particles involved in a reaction. By counting particles, you can get a better idea of how the reaction works at the molecular level, which is especially important in chemistry.