Oxides

Elements react with oxygen (aka. burn in oxygen) in the atmosphere to form oxides. Oxides are classified as: Acidic Basic Amphoteric Neutral   Acidic Oxides Acidic oxides react with water to form acids. Recall: Solutions of these acids in water have a pH value of less than 7. Acidic oxides are oxides of non-metals, which …

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pH Scale & Indicators

The pH scale (as shown in the figure above) is used to measure the acidity or alkalinity of an aqueous solution. The pH scale is numbered between 0 to 14. For reference, the equation for pH is given by: $$\text{pH} =-\text{lg} [\text{H}^{+}]$$ pH is given by the negative logarithm of the concentration of hydrogen ions …

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Physical & Chemical Properties of Alkalis

Physical Properties of Alkalis Alkalis have the following properties: Alkalis have bitter taste and a slippery soapy feel. Alkaline solutions have pH values greater than 7. (More about pH value in the next sub-topic) Alkaline solutions turn red litmus paper blue. Chemical Properties of Alkalis There are four common reactions of alkalis: Neutralisation reaction Reaction …

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Introduction To Bases

A base is a compound which, when dissolved in water, dissociates to produce hydroxide ions, $\text{OH}^{-}$ Alternative definition: A base is a metal oxide or hydroxide which reacts with an acid to form water and a metal salt only. Several examples of bases are as follows: Sodium hydroxide: $\text{NaOH} \rightarrow \text{Na}^{+} + \text{OH}^{-}$ Potassium hydroxide: …

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