In this lesson, Mr Teoh will not be around. Please promise to complete this lesson on your own and try your best! Please also read all feedback after each question!

Please also take out your notes for Chemical Calculation.

What is the relative atomic mass of oxygen atom?

How many dozen of eggs are there in this picture?

Below is an example of an equation:

a = b × c

What is c?

A packet of peanut weighs 200 g.

Each peanut weighs approximately 1.5 g.

How many peanuts are there in the packet?

Elephants are large mammals. Mice are small mammals. Elephants are afraid of mice.

If I have 1000 elephants and 1000 mice, are there more elephants or more mice?

I weigh my elephants and mice.

If I have 10 000 kg of elephants and 10 000 kg of mice. Which are heavier?

I weigh my elephants and mice and count the number of elephants and mice I have.

If I have 10 000 kg of elephants and 10 000 kg of mice. Do I have more elephants or more mice?

I want to find out the number of elephants in 10 000 kg. Each elephant weighs 1000 kg.

Which of the following shows the relation between 1. mass of elephants 2. number of elephants and 3. mass per elephant?

1 mol of carbon atoms weigh 12 g (This is the Ar of carbon!)

I have a container with 48 g of carbon atoms. What is the number of mol of carbon atoms?