This is another section in O Level Chemistry where students find it tough to comprehend. Lets reveal the Secrets here.
An oxide is a compound of Oxygen and another element (e.g. through the process of Combustion)
• Metals form Metal Oxides and Non-Metals form Non-Metal Oxides
• Oxides can be classified as either Acidic, Basic, Amphoteric or Neutral
• Nature of the oxides of the elements across the periodic table from left to right changes from Basic –> Amphoteric –> Acidic
SO2, SO3, CO2, NO2
1. Do not react with acids.
2. React with bases and alkalis to form salt & water.
3. Dissolve in water to form acidic solutions.
4. Usually gases at room temp.
Na2O, CaO, MgO, FeO, CuO
1. Do not react with bases.
2. React with acids to form salt & water.
3. Basic Oxides are usually insoluble in water. Those that dissolve in water forms alkaline solutions.
CO, NO, H2O
1. Neutral pH
Oxides formed with metals near “STEPS” such as ZnO, Al2O3, PbO,
1. React with both acids and bases to form salt & water
For those taking GCE ‘O’ Level syllabus, there are many questions that will come out for this section on Types of Oxides.
Let’s take a look at some exam-based questions.
Quick Check 1:
Which of the following reacts with dilute sulphuric acid to give a gas and water as two of the products?
B. zinc carbonate
C. zinc hydroxide
D. zinc oxide
Quick Check 2:
Which element forms an oxide that reacts with water to give an acidic solution?
Quick Check 3:
Which element burns in air to form an oxide which, when shaken with water, gives a solution with a pH greater than 7?
PS: Do leave your suggested answers in the “Comments Section” directly below this post.
PPS: This post belongs to a series of blogposts that is associated with Secrets of “Acids, Bases & Salts and Qualitative Analysis revelaed”