CHM102 Lecture Notes - Lecture 8: Vapor Pressure, Surface Tension, Heat Capacity
Stoichiometry in Solution
- Stoichiometry in solution works the same as you know how to do stoichiometry
problems already; the only difference is how you find moles.
- Instead of moles from grams, you will find moles from Molarity and Volume of a
solution
- Concentration of solutions is commonly expressed in molar:
The Remarkable Properties of Water
Density:
- Liquid water is more dense than the ice.
- The density-temperature curve shows a maximum at 4°C.
- As a consequence, in winter open water freezes on the surface and protects the
underlying water and aquatic life.
Specific heat capacity:
- By definition: the amount of heat required to raise the temperature of 1 g of a
substance by 1 K.
- The specific heat capacity of water is high compared to other liquids.
Enthalpy Change of Vaporization:
- Vaporization (evaporation) is the process in which a substance in the liquid state
changes to the gaseous state.
- Energy needs to be supplied for such process in order to break intermolecular
forces.
- The intramolecular forces (i.e., H−O bonds) are not broken and both liquid and
vapour are composed of H2O molecules.
- The amount of energy required to evaporate 1 mol of a substance is called the
molar enthalpy change of vaporization (ΔvapH).
- One mole of water requires much more energy than the same amount of other
common substances with similar size molecules.
Document Summary
Stoichiometry in solution works the same as you know how to do stoichiometry problems already; the only difference is how you find moles. Instead of moles from grams, you will find moles from molarity and volume of a solution. Concentration of solutions is commonly expressed in molar: Liquid water is more dense than the ice. The density-temperature curve shows a maximum at 4 c. As a consequence, in winter open water freezes on the surface and protects the underlying water and aquatic life. By definition: the amount of heat required to raise the temperature of 1 g of a substance by 1 k. The specific heat capacity of water is high compared to other liquids. Vaporization (evaporation) is the process in which a substance in the liquid state changes to the gaseous state. Energy needs to be supplied for such process in order to break intermolecular forces.
