Science lab concentration | Chemistry homework help
- This lab was adapted from an activity provided by: University of Colorado. (). PhET Interactive
Simulations - Physics, PhET: Interactive simulations. Retrieved at May 7, 2020, from the website https://phet.colorado.edu/en/contributions/view/4280 PHSC 1021 online 1 | P a g e Concentration part 1: Prelab
Objectives:
- Explore concentration and saturation as related to solvents and solutes.
- Calculate molar mass and mass of solute needed for a specific concentration.
Web link:
- PhET Concentration https://phet.colorado.edu/en/simulations/concentration
Introduction:
A mixture is a type of matter composed of varying proportions of two or more substances that are only physically mixed and not chemically combined. Mixtures can be divided into two categories – heterogeneous and homogeneous. A heterogeneous mixture is non-uniform so that at least two components can be observed examples include pizza and oil/water. A homogeneous mixture is uniform throughout like coffee or an alloy. Another name for a liquid, homogeneous mixture is a solution. A solution is composed of two parts 1) a solvent which is the liquid or the substance in the larger quantity, and 2) a solute which is the substance dissolved in the solvent. Figure 1 below shows two examples of salt-water solutions. In a salt-water solution, water is in the larger amount and is the solvent, while the salt is in the smaller amount and is the solute. At a given temperature only a certain amount of solute can be dissolved into the solvent. When the maximum amount of solute is present the solution is said to be saturated. Any extra solute added to a saturated solution would remain undissolved and usually settle at the bottom of the container. When less than the maximum amount of solute is dissolved into the solvent, the solution is called unsaturated. Figure 1: Two Examples of Salt-Water Solutions. -----------------------------------------------------------------------------------------------------------------------------