As you can see from the on-going survey on the right hand side, Mole Calculations (commonly known as Mole Concepts) has been voted by students as the #1 Killer Topic in O Level Chemistry (and other equivalent basic Chemistry Syllabus).
In fact, a large number of students skip the calculation-based questions when they see it on Chemistry examination, fearing that they spend alot of time on that question, and yet could not answer it.
Over the years, this topic is often voted the ?Hot Favorite? on students? challenging topics. Some:
- have problems understanding what the question is asking for
- do not know where to start
- totally blank when they read the question
- too confused with the formulae to use
- gave up on Mole Calculations totally
Many a times, question will require you to write a Balance Chemical Equation in order to solve the question. Other times, they will also require you to write the Ionic Equation and state the Spectator Ion.
As such you will need the following basic foundations that i have shared some time ago:
4 Steps-Process to write a Balanced Chemical Equation
7 Steps-Strategy to write the Ionic Equation & Spectator Ion
The best way to learn is NOT TO READ, but to DO IT!
Let’s try out one exam-based question(similar to O Level Chemistry Exams):
Question 1:
Copper (II) oxide reacts with dilute sulfuric acid to produce a salt, copper (II) sulfate and water. This process is known as Neutralisation.
i)? Write a balanced chemical equation with state symbols
ii) Write the ionic equation and state the spectator ion of this reaction
PS: Try it out and leave your answers below.