Arrhenius Theory Of Acids And Bases

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Theory:
A) In 1884, the Swedish chemist Svante Arrhenius theorized compounds would be classified into two different substances. These two substances are acids and bases. The Arrhenius Theory of acids and bases states that acids are substances that dissociate to form charged atoms known as ions. Bases ionize to produce hydroxide ions while acids produce hydrogen ions. HCl is an example of an Arrhenius acid because it dissociate into an H+ ion. The reaction involving NaOH is an example of an Arrhenius base because it is increasing the concentration of (OH-) ions.

The reaction which occurs is a neutralization reaction because the H+ and OH- ions react to form water.
H+ and OH- → H2O

The acidic behavior acids such as sulfuric, hydrochloric, and acetic acid and the basic properties of well-known hydroxides such as sodium and potassium hydroxide are explained and based on their ability to produce hydrogen and hydroxide ions. Acids and bases are classified as strong or weak acids and bases depending on the concentration of hydrogen and hydroxide ions produced.

The Arrhenius Theory however is not as extensive and has many limitations.

The Brønsted-Lowy Theory states that all acid-base reactions involve the transfer of an Hydrogen (H+) ion, or proton. Acids are "proton donors" while bases are "proton acceptors." The Brønsted Theory adds on to the Arrhenius Theory of Acids and Bases. It can be described as the transfer of protons from one substance to another substance. Hydroxide ions (OH-) are bases because they “accept” hydrogen ions from acids to for water. Acids produce Hydrogen ions (H+) which react with water molecules giving them a proton.

The diagram below depicts the reaction of HCl with NH3. In the reaction, HCl ...

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...ations served as background information for the calculations and for the general procedure of the lab. The solid acid, when added to water ionized to form charged particles causing the solution to have a certain pH that could be figured out from a titration curve graph. The acid used in this lab, KHP, ionized in water and formed Hydronium ions in the water. These ionized particles were what gave the acid a certain pH and those particles were what was being neutralized in the reaction. Multiple titrations were performed to neutralize the acid, in each titration, the lab groups attempted to reach the exact endpoint of the reaction without going over it. The endpoint was indicated by a slight color change in the solution to a pale pink color. When the endpoint was achieved, the calculations for the moles of acid to the moles of base were equal at that point.

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