A standard sometimes referred to as a stock solution is a concentrated solution that will be diluted for some laboratory use later on. And we're going to say dilution is just the addition of more solvent, usually water, to a solution in order to create a lower concentration.
So if we take a look here, we have our Purple Solvent, here purple solution. Actually, it's pretty dark purple, meaning that it's concentrated. And what we're doing here is we're slowly adding more water, so we're adding water to it to dilute it.
As a result of this, it goes from being a dark purple to a lighter type of fuchsia or purple. That's showing us that it's not as concentrated as it was before. So here, this represents our diluted solution. So just remember, when we're talking about dilutions, we're just talking about adding water to our original solution to make it less concentrated.