Specific surface area

Imagine you have two different types of candies: lollipops and Smarties. If you were to stack up a bunch of lollipops, they would take up a certain amount of space - let's say one square foot. However, if you were to stack up the same amount of Smarties, they would take up way less space because they are much smaller.

Now let's say we want to measure how much surface area there is in each of these candy stacks. Surface area is like the outside of the candy pile - it's the part that we can touch or see without cutting it open. To measure surface area, we need to know two things: how much candy there is, and how spread out or compacted the candy is.

To make this easier, let's imagine that we have a big candy mold that is one square foot in size. We can fill up this mold with either lollipops or Smarties and then figure out how much surface area is in each one.

When we fill up the mold with lollipops, there is a lot of empty space between each candy because they are big and bulky. This means that the surface area (the outer layer of candy that we can touch or see) is relatively small - let's say it's 5 square feet.

But when we fill up the mold with Smarties, there is very little empty space between each candy because they are so small and can fit together more tightly. This means that the surface area is much larger than the lollipops - let's say it's 50 square feet!

This is essentially what specific surface area measures - it's the amount of surface area in a given amount of material, taking into account how spread out or compacted that material is. So when we say that one material has a higher specific surface area than another, we mean that there is more outer surface area in a given amount of that material, compared to the other material.