Bio - Chapter 4 - Water and PH

A pH reading for a solution that has a greater concentration of hydrogen ions (H+) in solution than hydroxide ions (OH-). An acidic PH reading is any pH value below 7. The farther you move from 7 (neutral) on the acid side of the pH scale, the greater the hdyrogen ion cocentration.

One of the unique properities of water. Water is attracted to most other substances due to polarity of the water molecule and the charges found on the substance that is attractive to the polar water molecule. Capillary action demonstrates the attraction of water molecule (cohesion) to other water molecules, as well as, the walls of narrow capillary tube (ahesion)

A basic pH is a pH reading for a solution that has a greater concentration of hydroxide ions (OH-) in solution than hydrogen ions (H+). A basic pH reading is any pH value above 7. The farther you move from 7 (neutral) on the basic side of the pH scale, the greater the hydroxide ion concentration.

A compound that reacts with either acid or base to keep the pH of a solution essentially constant.

Individual water molecules are attracted to each other due to hydrogen bonds that form between water molecules. The hydrogen bonds form between the partially positive hydrogen end of the water molecule and the partially negative oxygen end of another water molecule.

A bond which results from the sharing of outer orbit electrons.

Ionic substances will dossociate or split apart into ions when placed in solution. For example: Table salt, NACl, is formed by an ionic bond. When Na Cl is placed in water, the molecule will dissociate into the ions Na+ and Cl-. Once the molecule has dissociated into ions, it is no longer the sodium chloride molecule. When ionic molecules dissociate in solution, the ions that result will conduct electricity. That is why ions are sometimes referred to as electrolytes.

Is one in which ions or electrolytes are present. The solution is called electrolytic because the ions have a charge and are able to conduct electricity through the solution.

Is the tendency of an atom in a molecule to attract shared electrons to itself. The oxygen atom is an atom that is highly electronegative. The hydrogen ends of the molecule each have a partial positive charge, while the oxygen end of the molecule has a partial negative charge in a water molecule.

Water occurs in three states - solid, liquid and gas. when energy in the form of heat is added to liquid water, the hydrogen bonds holding the water molecules togegther break, and the water evaporates into a gaseous state. we can observe this as a pot of boiling water evaporates.

When one molecule has a partially positively charged hydrogen atom, it may be attracted to another molecule that has a partial negative charge. This attraction is called a hydrogen bond.

An atom that has one proton and no electrons, therefore, resulting in a positive charge

Contains one oxygen atom covalently bonded to a hydrogen atom and has an overall charge of -1.

Any atom of group of atoms that has an overall charge of either positive or negative

To seperate into ions