Tag Archive: Elements Compounds & Mixtures

O Level Chemistry – Mini Series on Tough MCQs Part 2

Continue with Chemistry Tips

From the previous post, we have started on our Mini Series on Tough MCQs.

Purpose is to enquire that students are exposed to tougher & tricky chemistry Multiple Choice Questions (Paper 1) that we have observed for the last 10 years.

How come i know them, you may asked? Cos i have been compiling and analyzing these questions for my students year-after-year, and sharing with them to ensure that they know how to avoid the common mistakes and traps that many other students have fallen into.

You know what – Usually this “tough” questions are Application Type Questions that just need a cool head and good chemistry concepts to get it right. It isnt that tough at all.

Let’s continue with more questions below:

Question 1:
Why is Sodium classified as Metal?
a) It is a pure substance
b) It is a good conductor of electricity
c) It exists as atoms, not molecules
d) It is very soft

Question 2:
Buckminsterfullerene was discovered in 1985 and it has a perfect sphere with formula C60. From this information, what can you deduce about it?
a) It contains only one element
b) It is a compound of 60 elements
c) It is a mixture of 60 atoms
d) It is a mixture of 60 elements

Question 3:
When mercury is heated, it forms mercury and oxygen,

Mercury oxide (s) –> mercury (l) + oxygen (g)

What can you deduce from the above information?
a) During the heating of mercury oxide, all three states of matter exist
b) Mercury oxide is a mixture
c) Mercury oxide is a silver solid
d) The composition of mercury oxide varies during heating

PS: Try out the questions and enter your suggested answers (and comments) right below, so that others can come in to share their answers and thought process.

O Level Chemistry: Element, Compounds & Mixtures

Another question on Elements, Compounds & Mixtures that i have discussed with the students in my Intensive Revision Program. Thought it will be an interesting one for you to try it out.

The elements iron and sulfur combine to form the compound iron sulfide (FeS). List the differences between Iron Sulfide and a mixture of iron and sulfur. (Tips: You can present in a table format)

All the best to your Academic Success in Chemistry,

PS: Check “Comments” below for Suggested Answers.

O Level Chemistry: Element, Compounds & Mixtures

Q) Explain why air is considered a mixture & not a compound or element?

Do show us your reasoning as much as possible.


PS: Check “Comments” below for Suggested Answers.