Chemistry question about basis of dilution

Question

The fundamental basis of the dilution equation is the idea that ______________________ .

1. the amount of solute stays constant.
2. the amount of solvent stays constant
3. the solute is soluble in any amount of solvent
4. the solute can dissolve in more than one solvent
5. the temperature of the solution stays constant

Answer 1

The amount of solute stays constant. This means if you know how many grams or moles of "stuff" you have dissolved, you can add any amount of solvent and that "stuff" doesn't change. It just gets more dilute as you add more solvent.

Think about it this way - if you put a spoonful of salt into a small cup of water, you have some salty water! If you add a gallon more water, the spoonful of salt is still in there, and you didn't add any more salt - but you added a bunch more water. So that same (constant) amount of salt (solute) is in the solution, regardless of how much water (solvent) you add. Hope that helps!