Chemistry: Acids and Base Theories

INTRODUCTION

Acids and bases always challenged me throughout the years of learning them so when I learned I am going to face this topic again I thought it will be the best idea to a experiment for learning better therefore my aim for this project was learning the fundamentals of this topic.

Acids and bases are really important in functioning cell. Majority of them are harmful and they destroy tissues by dissolving protein. For example, sulfuric acid is a strong acid and it has ability to hold the water therefore if it poured on a live tissue it will be demolished immediately. Aqueous solutions of bases reacts with fat in cell membrane this makes bases more devastating to an organism than acids. Acids and bases aqueous solutions conduct electric. Acids tastes sour, bases tastes bitter and bases are slippery. Strength of an acid or a base depends on its ionizing rate. Strong acids and bases are ionized completely therefore they have pH or pOH of 1, weak bases and acids doesn’t ionize completely so they have a ph or pOH of 3-5.

Acid and Base Theories

Until today acids and bases defined in many different ways but first modern description is done by Swedish scientist Svonte ARHENIUS in 1884. He said,

Aqueous solutions of acids give H+ ion. For example:

NaOH → Na+

+ OH−and

Aqueous solutions of bases give OH- ion for example

NaOH → Na+

+ OH−

Second description of acids and bases is found by Danish chemist J.N. Bronsted and English chemist in T.N LOWRY in 1923. According to them matter that gives protons are acid and matter that receive proton is base. With this description matters that aren’t thought to be an acid or base is now classified as an acid or a base. For example Boron trifluoride is act as an acid an...

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...rstood titration is neutralization reaction.

In acid-base titration solution without a known molarity is placed in an Erlenmeyer after it’s volume is measured. An indicator is added to the solution most of the time it is phenolphthalein. The solution with a known concentration is placed in burette with a tap in the end. By opening the tap slightly solution in the burette is poured in to the solution in Erlenmeyer drop by drop. After a while the solution in Erlenmeyer forms a color change. This is the turning point for the solution. At the turning point by the volume consumed in burette the molarity of the other solution can be

Indicators

Indicators are substances that change color according to the acidic and basic properties of their surroundings. There are many different indicators that shows different pH levels and some are beyond in the table.