Handout four            Handout on forces and        What’s Cookin

 

Gas:  A fluid form of matter that takes both the volume and shape of the container it occupies.  

Liquid:  A fluid form of matter that takes the shape of the part of the container (volume) it fills.

Solid:  A rigid form of matter that maintains its shape in any container it can fit.

 

Vapor Pressure:  The pressure of the vapor over a liquid at equilibrium.  The distinction between a gas and a vapor is as follows:  a gas is a substance at a higher temperature than its boiling point, a vapor is a gaseous form of matter at a temperature below its boiling point.

 

 

Intermolecular Forces

 

London Dispersion Forces:  The force of attraction between that arises from the interaction between two instantaneous dipoles on neighboring molecules.  This attraction occurs in all molecules but is only important in non-polar molecules.  A short range  weak intermolecular interaction.  Less than

Dipole-dipole interactions:  An electrostatic force that results when the positive and negative end of polar molecules are attracted to one another.

Dipole:  Any object whose ends carry opposite but equal charges. 

Hydrogen Bonding:  The attraction between a hydrogen atom bonded to an electronegative oxygen or nitrogen atom and another nearby electronegative O, N (Cl), F atom.

 

solutions:  A homogeneous mixture of two or more substances in a single phase. 

 

solvent:  The most abundant component of a solution.  This is the medium in which the solute(s) is dissolved.

 

solute:  The material dissolved in a solution.

 

hydrophilic:  water loving

hydrophobic:  water fearing

 

Molarity:  The number of moles of solute per liter of solution.

 

Normality:  The number of chemical equivalents of solute per liter of solution.

 

Colligative Properties:  Properties of a solution the depend only on the number of solute particles per solvent molecules and not on the nature of the solute or solvent.  These include vapor pressure lowering, freezing point depression (FPD) and boiling point elevation (BPE).