LESSON 5: Concentration of Solutions

• Solution


  A homogenous mixture of two or more substance
• Solute


  the substance that is dissolved in a solvent
• Solvent


  the substance in which a solute dissolves, usually present in the greatest amount
• Dissolution


  process where a solute is gaseous, liquid or solid phase dissolves in a solvent to form a solution
• Solubility


  The maximum concentration of a solute that can dissolve in a solvent at a given temperature
• Solute has a higher boiling point compared to solvent
• The physical state of solute can be solid, liquid or gaseous, whereas solvent in mainly in the liquid state, but can be gaseous as well.
• Concentration


  refers ti the amount of substance in a defined space. The ratio of solute in a solution.
• Molarity


  a unit of concentration expressed as the number of moles of dissolved solute per liter of solution
• Molality


  total moles of a solute contained ina kilogram of a solvent. Also known as molal concentration
• Mass percent


  ratio of mass of solute that is present in a solution, relative to the mass of the solute as a whole
• Volume percent


  ratio of the volume of solute that is present in a solution
• Mole fraction


  The number of moles of a specific component in the solution
• Molarity depends on the volume of the solution since the volume of a solution changes with the change in temperature and pressure.
• Molality is an intensive property of solutions, it only depends on the mass of solvent, hence it does not change with temperature and pressure.
• Molarity is defined as the number of moles of a solute that are dissolved in 1 liter of a solution
• Molality is defined as the number of moles of a solute that are dissolved in 1 kg of a solvent.
• • Molality is a more precise and accurate means of making a certain concentration because it is unaffected by temperature and pressure changes.
• • Molarity involves a liquid which means that the concentration can change. This is because the volume being a liquid can change with changes in temperature and pressure.