Equilibrium+and+Acids+&+Bases

The use of indicators in determining ph: An Indicator does not change color from pure acid to pure alkaline at specific hydrogen ion concentration, but the color change occurs over a range of hydrogen ion concentrations. This range is calledthe color change interval. It is expressed as a pH range. [] [] Who invented the system of measuring ph? -  The concept of pH was first introduced by Danish chemist Søren Peder Lauritz Sørensen at the Carlsberg Laboratory in 1909. Sørensen suggested the notation "PH" for convenience, standing for "power of hydrogen", using the cologarithm of the concentration of hydrogen ions in solution, p[H]

Read more: [] Reversible reactions When the equilibrium state is in significant quantities of both reactants and products are present, then the reaction is //incomplete// or reversible. []

media type=\ width="480" height="385"Equilibrium and Acids & Bases= [] [] [] (Glencoe Science - Chemistry: Matter and Change pg 981) (Glencoe Science - Chemistry: Matter and Change pg 981) [|http://medical-dictionary.thefreedictionary.com/PH+indicator] [] [] The Equilibrium Constant --- [] (Glencoe Science - Chemistry: Matter and Change pg 983) Quiz testing knowledge on Le Chatelier's Principle: [] [] citation []
 * Key Terms:**
 * media type=\ width="425" height="350"Arrhenius acid -**a substance that when added to water increases the concentration of H1+ions present
 * Arrhenius base-**a substance that when added to water increases the concentration of ions OH1-present
 * Bronsted lowry acid-** any substance that can dontate a hydrogen ion (proton)
 * Bronsted lowry base-**any substance that can accpet a hydrogen ion (proton)
 * Hydronium ion-**result of the combination of a water molecule and a proton
 * pH-** the negative logarithm of the hydrogen ion concentration of a solution; acidic solutions have pH values between 0 and 7, basic solutions have values between 7 and 14, and a solution with a pH of 7.0 is neutral.
 * pOH-** the negative logarithm of the hydroxide ion concentration of a solution; a solution with a pOH above 7.0 is acidic, a solution with a pOH below 7.0 is basic, and a solution with a pOH of 7.0 is neutral.
 * pH indicator-** A substance that indicates the degree of acidity or basicity of a solution through characteristic color changes.
 * Equilibrium-** The condition in which all acting influences are balanced or canceled by equal opposing forces, resulting in a stable system.
 * Reversible reaction-** a reaction that can take place in both the forward and reverse directions; leads to an equilibrium state where the forward and reverse reactions occur at equal rates and the concentrations of reactants and products remain constant.
 * Le Chatelier's Principle-**chemical principle that states that if a system in equilibrium is disturbed by changes in determining factors, such as temperature, pressure, and concentration of components, the system will tend to shift its equilibrium position so as to counteract the effect of the disturbance
 * Electrolyte-** An electrolyte is a substance that will dissociate into ions in solution and acquire the capacity to conduct electricity. The electrolytes include sodium, potassium, chloride, calcium and phosphate.

Properties Of Arrhenius Acids And Bases:
One of the properties that acids and bases have in common is that **they are electrolytes**--they form ions when they dissolve in water. []

The H1+ ion produced by an Arrhenius acid is always associated with a water molecule to form the hydronium ion, H3O1+(//aq//). Arrhenius acids are frequently referred to as proton donors, hydrogen ion donors, or hydronium ion donors, depending on whether we are trying to emphasize the species liberated by the acid (proton or hydrogen ion) or the species present in solution (hydronium ion). To represent the transfer of the H1+ ion to water to form the hydronium ion, we must include H2O in the chemical equation for acid ionization.



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//**The Arrhenius Definition of Acids and Bases:**// In 1884, Svante Arrhenius suggested that salts like NaCl separate when they dissolve in water to give particles that he called **ions**

[] **Reversible Reactions and Equilibrium** In some reactions, no products is allow formed to allow the reaction to go to completion, that is, the reactant and products can still reacts in both directions. this can be shown as follows:A+B<--> C+DA real chemical example would be:H2+I2<--> 2HIin which the rate of the forward reaction is equal to reverse reactionthe double arrow indicates that C and D can react to form A and B, and same thing with A and B.[]# = Bronsted-Lowry:acids and basis and equation = = media type=\ width="480" height="385" align="center"
 * || H2O ||  ||
 * NaCl(//s//) || [[image:http://chemed.chem.purdue.edu/genchem/topicreview/bp/ch11/graphics/rarrow.gif width="17" height="9" caption="->"]] || Na+(//aq//) + Cl-(//aq//) ||

= In some reactions no products is formed to allow the reaction to go to completion, that is, the reactants and products can still interact in both directions. This can be shown as follows:In some reactions no products is formed to allow the reaction to go to completion, that is, the reactants and products can still interact in both directions. This can be shown as follows: In some reactions no products is formed to allow the reaction to go to completion, that is, the reactants and products can still interact in both directions. This can be shown as follows: Describe the use of indicators in determining pH: http://www.chemguide.co.uk/physical/acidbaseeqia/indicators.html This page describes how simple acid-base indicators work, and how to choose the right one for a particular titration.

Bronsted lowry acids and bases: It's goes from simple to complicate ways for testing any substances are acid, base nor neutral. The Bronsted-Lowry definition is named for Johannes Bronsted and Thomas Lowry, who independently proposed it in 1923. A Bronsted-Lowry (BL) acid is defined as any substance that can donate a hydrogen ion (proton) and a Bronsted-Lowry base is any substance that can accept a hydrogen ion (proton). Thus, according to the BL definition, acids and bases must come in what is called //conjugate pairs//.

Bronsted lowry acids and bases: a Bronsted-Lowry acid is a material that gives up hydrogen ions during a chemical reaction. [] =__**Indicators and pH**__= media type=\ width="480" height="385" media type=\ width="480" height="385" [] This is website of the game for chemistry from beginer to master. It is pretty fun and "hard". []
 * john dalton read more in the link

=How to Calculate pOH and pH= Calculate the pOH and pH at 298K of solutions considering the following ion concentrations. OH = 1.3 times 10 to the negative 2 power M.

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 * __Arrhenius Acids__**
 * __Arrhenius Bases__**
 * __Identify acids/base pair in given acid/base reaction__**

Classify a solution as acidic, basic, or neutral given its pH. The pH scale is what measures how acidic or basic a certain substance is. The pH scale ranges from 0 to 14. A pH of 7 is neutral. A pH lower than 7 is acidic. A pH greater than 7 is basic. Pure water is neutral, but when chemicals are mixed with water, the mixture can become either acidic or basic. Some examples of acidic substances are vinegar and lemon juice. Lye, milk of magnesia, and ammonia are also some examples of basic substances. [] Another Lewis Acid/Base Reaction Info: []media type="youtube" key="iton8L8Gg_w?fs=1" height="385" width="480" Le Chatelier's Principle to predict the effects of changes in temperature, pressure, and concentration []

Classify a solution as acidic, basic, or neutral given its pH: Vinegar pH:2.40-3.40 Acid or Base: Why? Vinegar is an acid. It is composed of about 5% acetic acid --> CH3COOH Games about acid and base quiz from beginner to high level: []

[] : practice for determine the Ph of each solution

[]: Acids, Bases, pH, aqueous: Acids and Bases (pH scale) Quiz, this is fun game! Acid and bases can be put on a scale.