Chem
Chapter 5: Solutions, Colloids, and Membranes
Chapter Summary
Mixtures and Solutions * A mixture maintains its identity regardless of the proportions of its components. * A mixture can be separated into its pure components through physical separation techniques. * The components are distributed uniformly throughout a homogenous mixture. * The components are not distributed uniformly throughout a heterogeneous mixture. * A solution is composed of a solvent and one or more solutes. The solvent is present in the greater amount. In an aqueous solution, water is the solvent. * Polar solvents tend to dissolve polar solutes, and nonpolar solvents tend to dissolve nonpolar solutes. * When a molecule dissolves in solution, the chemical bonds of the molecule remain intact. * When an ionic compound dissolves in solution, the lattice dissolves and the ions are surrounded by water molecules. * An electrolyte is an ion dissolved in water.
Solution Concentration * Concentration is expressed as a ratio: The amount of solute is the numerator and the total amount of solution is the denominator. * The most commonly encountered units of concentration in the medical field are mass/volume, %mass/volume, moles/volume, and equivalents/volume.
Colloids and Suspensions * Colloids contain particles that are much larger than typical solute particles. * Suspensions are mixtures in which particles are unevenly distributed throughout the medium, and eventually settle.
Membranes, Osmosis, and Dialysis * Substances can move across a semipermeable membrane through osmosis and dialysis. * Osmosis and dialysis regulate the distribution of nutrients in the cell and the removal of waste products from the cell. * Simple diffusion is the spontaneous movement of a molecule or ion from a region of higher concentration to a region of lower concentration. * In osmosis, water crosses a semipermeable membrane by simple diffusion
Chapter Summary
Mixtures and Solutions * A mixture maintains its identity regardless of the proportions of its components. * A mixture can be separated into its pure components through physical separation techniques. * The components are distributed uniformly throughout a homogenous mixture. * The components are not distributed uniformly throughout a heterogeneous mixture. * A solution is composed of a solvent and one or more solutes. The solvent is present in the greater amount. In an aqueous solution, water is the solvent. * Polar solvents tend to dissolve polar solutes, and nonpolar solvents tend to dissolve nonpolar solutes. * When a molecule dissolves in solution, the chemical bonds of the molecule remain intact. * When an ionic compound dissolves in solution, the lattice dissolves and the ions are surrounded by water molecules. * An electrolyte is an ion dissolved in water.
Solution Concentration * Concentration is expressed as a ratio: The amount of solute is the numerator and the total amount of solution is the denominator. * The most commonly encountered units of concentration in the medical field are mass/volume, %mass/volume, moles/volume, and equivalents/volume.
Colloids and Suspensions * Colloids contain particles that are much larger than typical solute particles. * Suspensions are mixtures in which particles are unevenly distributed throughout the medium, and eventually settle.
Membranes, Osmosis, and Dialysis * Substances can move across a semipermeable membrane through osmosis and dialysis. * Osmosis and dialysis regulate the distribution of nutrients in the cell and the removal of waste products from the cell. * Simple diffusion is the spontaneous movement of a molecule or ion from a region of higher concentration to a region of lower concentration. * In osmosis, water crosses a semipermeable membrane by simple diffusion