3N: The Mole Concept

What is a mole?

To a biologist, a mole is an animal:

To a plastic surgeon, a mole is a bodily imperfection:

But to a chemist, a mole is a unit of measurement.

SI unit: mole
Symbol: mol
Definition: Amount of substance containing 6 x 10²³ particles

Why do we need this mole concept?

The mole concept enables us to calculate the amount of chemicals needed to make our clothing, food, drinks, toothpaste, medicine, printer inks and almost everything that has been manufactured.

What are the ways to measure a substance's mass?

There are three ways:

Relative atomic mass (A_r): 

• average mass of 1 atom compared to 1/12 of the mass of carbon-12 atom
• find directly from the Periodic Table
• no units

Relative molecular mass (M_r):

• average mass of 1 molecule compared to 1/12 of the mass of carbon-12 atom
• need to know chemical formula first, then sum up the A_r of all the atoms present in the compound
• no units

molar mass:

• mass of 1 mole of substance
• equivalent to A_r and M_r, but with units
• units: g/mol

What is the formula you need to know?

Have fun with the numbers!

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Why Study Chemistry?

Have you ever wondered what makes up the food that you have been putting into your mouth? Or how your latest handphone works? Chemistry is the fascinating study of what we eat, how we live and why certain chemicals come together in strange and wonderful ways.

Here are more reasons why you should elect to study this scientific field:

1) Because our schools don't offer Potions classes and the closest alternative is Chemistry.

In the labs, you get to mix, heat, burn, boil, cool, freeze, test and purify all kinds of interesting materials. There will be colour changes, from pale sky-blue to deep coral purple. There will be smoke, fires (while observing your personal safety at all times!) and pungent gases.

2) You'd finally discover what chemicals (or drugs) you've been eating all along.

The next time you walk into a supermarket, you can pick up an orange and tell your friends, "there's citric acid in this fruit." To top it off, you can even list all the properties of an acid! Everyone will be so impressed by the extent of your knowledge that they yearn to be your best buddies. 

3) You'd be able to understand lame science jokes.

Suddenly, all the strange comments that your teachers have been saying, well, suddenly, they all make PERFECT SENSE.

4) Or even make come up with even lamer ones yourself:

5) The world becomes more friendly when you understand the scientific ways in which it functions. 

Science equips you with the knowledge and perspectives to understand the people, places and phenomenon around you in wondrous new ways. 

6) You might get the chance to tinker with expensive gadgets that will produce beautiful images.

This catalyst is like a rose with thorns.

7) You don't really want to study other subjects. So, might as well study Chemistry, right?

Now, pay attention in class.

8) At times, you may even get to see equivalents of shooting stars.

Images credit: Angelo State University

8) Most importantly, you learn to defend yourself from cheats, hacks, charlatans, scammers and liars. They may tell you that certain stones can cure cancers, offer good luck and grant excellent grades, if only you'd pay them. DO NOT TRUST THEIR LIES.

 

Learning should be great fun. It should be awesome and exciting. This is all the more so for the study of Chemistry. There are so many reasons why we should enjoy this scientific adventure.

All the best on this journey towards understanding and appreciating the laws underlying this world that all of us live on.  

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Ask yourself: why are you studying?

Listen to the Mustn'ts, child, listen to the Don'ts.
Listen to the Shouldn'ts, the Impossibles, the Won'ts.
Listen to the Never Haves, then listen close to me.
         Anything can happen, child, Anything can be.

- Shel Silverstein

Do you ever wonder why you’re studying and for whom? Is it to make your parents happy? Or to stop your teachers from nagging?

Is it to keep up with your friends? Or do you fear not doing well and being deemed as an ignorant fool?

Maybe it’s because you don’t know what else to do with your precious time, energy and resources? Or is it precisely because you know what you want to do that you’re putting in so much effort?

The truth is, there may be many reasons why you need/want to study. Some of these reasons are dependent on the people around you. While it’s good to put in effort because you care for others and how they think, it’s even better to study because you wish to satisfy your own curiosity.

Ultimately, why you study depends on yourself and the fruits you harvest belong to you too. By learning and questioning what you learn, you allow yourself to strengthen and grow, like a tender sapling nourished by droplets of ideas and information.

Be excited about your learning and your excitement will bring you a magical joy.

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All the best this week :]

Here're some quotes to keep you going as a new week brings fresh hopes, challenges and fulfillments!

Remember that you've the spark of greatness within. Also, remember that you must nurse this spark into a ball of energy and lightning such that you may and would build a better future for everyone!

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Upfront! with Tan Kai Soon, Person Moving On!

Image credit: Google

Sometimes, we don’t recognize that what we’ve is precious. Studying may be a daily chore. Walking briskly from one point to another is easy. Taking a bath doesn’t require much effort. We take for granted what we should treasure.

When I first heard of Kai Soon’s academic journey, I wanted to speak to him, to know what he had been through. I wished to find out how an EM3 student eventually achieved an NTU degree despite suffering from progressive muscular dystrophy.

What I found out was more – much more – than what I intended to or imagined would. Thanks, Kai Soon, for sharing your story:

I’m so sorry about this, Kai Soon, but I’m not really sure what the symptoms of muscular dystrophy are. Can you please explain it?

It means that my muscles are wasting away over the years.

When I was younger, I didn’t know that I’ve a muscular disorder. My primary school teacher thought that I had flat foot. I struggled for the NAFA test. I was always tipping and falling for no good reason. Some classmates laughed at me because I took a long time to stand up.

It was hurtful, especially since I had no idea why.

Nowadays, I can thankfully still bathe myself. Ten years down the road, as my body grows weaker, I may not be able to do so.

When did you first realise that you’ve progressive muscular dystrophy?

When I was studying in the Institute of Technical Education (ITE), I was diagnosed with this disease. The doctor recommended surgery so that I could walk better.

However, due to my muscle condition after the surgery, I am unable to walk as before and have to rely on the wheelchair to move about now.

For a while, I stayed at home and excluded myself from all social activities.

Thankfully, I’ve very supportive friends and lecturers from ITE.

So, Kai Soon, how had your education journey unfolded?

It was a long journey. EM3, Normal (Technical), ITE (known as Nitec and Higher Nitec after recent curriculum changes), Polytechnic, NTU.

In primary school, I was from the EM3 stream. In secondary school, I was placed in a Normal (Technical) class. I then moved on to achieve an ITE Nitec in Computer Technology and Higher Nitec in Electronics Engineering. Halfway through my Higher Nitec course, I was diagnosed with progressive muscular dystrophy, went for that life-altering surgery and became wheelchair-bound. For a while, I was really upset.

Thankfully, my friends supported me. One lecturer kindly drove me to and fro school for the remaining six months of the Higher Nitec course.

During my ITE days, I discovered the best way to study –

Really? What’s the best way?

There’s no shortcut. Flip through the pages. Study consistently. Spend every moment wisely.

Sorry for interrupting. What about the ITE?

Well, I studied Boodlean algebra then. That topic gave me the courage to believe in myself. If I could solve such algebra questions, I should be able to solve questions on easier topics. From then on, I found studying more manageable.

With my ITE grades, I qualified for a Singapore Polytechnic diploma course. I then moved on to complete an honours degree in Nanyang Technological University (NTU), majoring in Electronics and Electrical Engineering.

Just for interest, why NTU though?

NTU was the first school to offer me a place and, considering that it is more accessible for wheelchair users, I accepted it immediately.

So, after graduating, where did you work?

I applied for work at DSTA and did not manage to get it due to the physical requirement of the job. Actually, I wanted to serve National Service but was turned down as well. In the U.S., they have support such that even physically handicapped people can contribute. How I wish that this is the case too in Singapore.

In any case, I worked for a call center for eight months before I was hired by Asian Women’s Welfare Association (AWWA) as part of the support staff.

AWWA has been very helpful. They sponsored a significant portion of my university education loan under the bond-free Be With Me Scholarship. This relieved my financial burden. Currently, AWWA provides me with free physiotherapy once a week – as an employee benefit – to delay my muscular degeneration. Hopefully, it can stretch the period during which I have some form of control over my hands.

Kai Soon, there are so many students who don’t know why they’re studying. They sit in the classrooms – physically there but aren’t really there. They’re tired early in the morning, after assembly, tired before recess, tired after recess, tired before lunch, tired after lunch and tired before going home. In fact, they are listless the entire day! It’s such a shame that the students don’t recognize how precious an education is, the doors that education opens and the opportunities it provides. Do you have any advice for them?

Usually, people with my background would have been out of the education system quite early on. I’m thankful for the chance to get a university education.

And I understand why they feel this way. They’ve no reason motivating them to put in effort. In some ways, no future they can look forward to.

I’ve friends who now tell me that they regret not putting in more effort for their studies. It may sound overused but people do regret not studying harder when they could.

In our lives, opportunities present themselves. Quite often, I didn’t know whether I could make it or not but I wanted to try. When I applied for my polytechnic and university courses, I didn’t know if I could get in. I tried – put in effort and really tried. In the end, I managed to.

Students should believe in themselves, cherish what they’ve and strive for what they want.

Last question – were you ever angry about your condition?

Yes, I was once resentful – how could I not be? Over time, I’ve gotten used to the staring though. I am who I am. You are who you are.

We’re all responsible for our future. What we do now will affect what that will occur. To be honest, I always envisioned myself as an F1 driver. There are many junctions in life. The routes are long and winding. However, along these journeys, opportunities will present themselves. What we need to do is to treasure them.

Thanks, Kai Soon, for sharing. Really appreciate this candid chat.


I reached out to Kai Soon and realized that we couldn’t shake hands. I could only thank him profusely with words and hope that words would suffice.

I had set out to learn more from Kai Soon, to discover lessons that I could share with some students who need help. During the chat, I was humbled and understood more about what that should be important.

Often, we sacrifice what we’ve most willingly, as though it doesn’t matter. We give away what that is precious – our time, our energy, opportunities to study or work or serve national service. We take what we have for granted as though we couldn’t care less.

This really shouldn’t be the case. Once again, thank you, Kai Soon, for sharing your journey.

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On Happiness

"Happiness isn't coins that you can save and spend.

You cannot withold the feeling, imaging that one day, some day, you'll experience all of it at one go. It isn't like pieces of sweets. It isn't a holiday or home that you save up for. By not feeling joy today, do you imagine that you can save it up and experience ecstasy in a distant future?

It cannot be delayed. It cannot be saved then spent.

It requires practice. You learn to be happier by feeling incrementally joyful each day. It is a muscle that must be exercised, lest it atrophy.

Learn to be happy. For only in learning so, will you be happy."

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Using the Syllabuses

A respected teacher once asked, "how many of you actually read your syllabuses before?" The class was quiet. A few students raised their right hands hesitantly. About 20% of them have read their syllabuses. 

"Now, let's take a look at your syllabus. There is a point-by-point explanation of what you are supposed to know. Which facts to remember, what diagrams to draw, why certain reactions take place. Do you all see why it is important for you to read the syllabuses? People who read them know what may be tested. As a result, they are better prepared for their exams and, in general, do better."

We should learn because we are interested in learning. However, there are school exams calibrated to test our understanding and to do well for them requires strategizing, like playing football games. We need action plans to help us do well, in this as well as in other endeavors.

As such, every student is highly encouraged to download and print the syllabuses for their personal references.

Read through them, know what will be tested. Before major examinations, use them as checklists. Tick against points that you're confident of scoring in. Highlight areas that you need to work on and revise these topics. Study smartly!

All the best for every exam and beyond :]

Source credit: SEAB

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