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Acid and Bases. -Types of Oxides-. Many acids and alkali are formed by dissolving oxides in water. At the end of this e-learning, you should able to:. Classify oxides as acidic, basic, amphoteric or neutral based on metallic/non-metallic character. What is an oxide?.
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Acid and Bases -Types of Oxides- Many acids and alkali are formed by dissolving oxides in water
At the end of this e-learning, you should able to: • Classify oxides as acidic, basic, amphoteric or neutral based on metallic/non-metallic character
What is an oxide? • An oxide is a compound of oxygen and another element. • Most oxides can be grouped into four types: • acidic oxides • basic oxides • amphoteric oxides • neutral oxides
Acidic oxides • Oxides of non-metal • Acidic oxides are often gases at room temperature.
Acidic oxides • React with water to produce acids. • Example: sulphur trioxide + water sulphuric acid SO3 + H2O H2SO4
Acidic oxides • React with bases and alkalis to produce salts • Example: carbon dioxide + sodium hydroxide sodium carbonate + water CO2 + 2NaOH Na2CO3 + H2O
Basic oxides • Oxides of metal • Basic oxides are often solids at room temperature. • Most basic oxides are insoluble in water. Calcium oxide (quicklime)
Basic oxides • React with acids to produce salts and water only. • Example: Magnesium oxide + hydrochloric acid magnesium chloride + water MgO + 2HCl MgCl2 + H2O This is a neutralisation reaction
Amphoteric oxides • Oxides of metal • Can behave as acidic oxides or as basic oxides Zinc oxide
hydrochloric acid aluminium chloride aluminium oxide + + water aluminium oxide sodium hydroxide sodium aluminate + water + Amphoteric oxides • React with acids and alkalis to produce salts • Example: aluminium oxide (Al2O3) • aluminium oxide as a base • aluminium oxide as an acid
Neutral oxides • Non-metals that form oxides that show neither basic nor acidic properties. • Insoluble in water.
How can we classify an unknown oxide? First question: Does the oxide dissolve in acid? YES NO
It is either a basic or amphoteric oxide. Next question: Is the oxide soluble in alkali? Soluble Insoluble
It is either an acidic or neutral oxide. Next question: Is the oxide soluble in alkali? Soluble Insoluble
Amphoteric oxide What is an amphoteric oxide? Back to first question
Basic oxide What is a basic oxide? Cook an egg with calcium oxide Back to first question
Acidic oxide What is an acidic oxide? How does acidic oxide affects the atmosphere? Back to first question
Neutral oxide What is an neutral oxide? Back to first question Back to the first slide