Physical Quantities and Units

On 11 February 2014, my teacher taught us about physical quantities and units!

We learned that Observations and Variables are part of Physical Quantity,

So, what is physical quantity? Well, physical quantity can be measured and is made up of a base quantity and derived quantity.

Base Quantities are the building blocks of other physical quantities, such as metre, kilogram and etc.

So, the BASE QUANTITY, is also the SI unit (Symbol for Unit)

Derived Quantities are derived from base quantities through defining and equation.

As such, we need to have prefixes to represent the gigantic  numbers and the very small numbers.

For example, we have prefixes such as "Tera" and "Giga" to describe large. and also "micro" and "milli" to describe very small numbers.

So, why do have Prefixes? Feel free to click on the links below!

http://www.youtube.com/watch?v=0fKBhvDjuy0&list=PLE3A4122C317C2CE7 

http://www.youtube.com/watch?v=vRjGarICal4&list=PLE3A4122C317C2CE7

 Lastly, we also learned about unit conversion. 

http://www.purplemath.com/modules/metric.htm 

 

Graphing Scientific Data

On 22 January 2014, we learned about how to graph scientific data.

Firstly, we learned about interpolation and extrapolation.In simple terms, interpolation is just a method used to approximate values that are between points of a graph, while extrapolation is a method for approximating values that are beyond the range of the measurements obtained.

So firstly, there is the BEST-FIT LINE. The best-fit line is basically a line that has roughly the same amount of points on each side of the line.

Secondly, there is a more advanced type of line, which is called the  "Best Fit Curve". As the name suggests, we draw a smooth curved line through the points, not a straight line.

Science Laboratory Lesson "Boiling Point of Water"

On 5 February 2014, we conducted an experiment regarding the boiling point of water, as mentioned in the above header.

Firstly, we learned how to read the thermometer properly, in which it is essential that the eye be at the same level as the mercury meniscus, so as to prevent parallax error.

Secondly, we carried out the experiment and we recorded the experiment results, placing the raw data into the tables. However, we noticed that the water had some impurities as the water boiled at 101.5 degrees Celsius.

Afterwards, we plotted the results on a graph, joining the points with a best fit curve, and we also learned how to make accurate predictions from the graph.

2nd Science Laboratory Lesson ==>Making Observations

On 29 January, I had my 2nd Science laboratory lesson! The topic was on "Making Observations".

Therefore, we conducted a lot of mini-experiments and wrote down all our observations!

Well, the first experiment listed on the worksheet was not that interesting. It was to pour vinegar into a clean test tube to a depth of about 1cm, before adding a spatula of sodium bicarbonate. The observation was very intriguing though.  The water level of the vinegar rose before falling, and bubbles also appeared in the vinegar! Apparently, the explanation for this observation was that the sodium bicarbonate dissolves to form a colorless solution. Effervescence ( is the escape of gas from an aqueous solution and the foaming or fizzing that results from a release of the gas.) of a colorless and odorless gas was thus seen. 

For the second experiment, it was really interesting! We had to quarter fill two clean test tubes with water. Add a spatula full sodium carbonate to one test tube. Shake the test until the sodium carbonate dissolves. 

==> The observation was that the sodium carbonate dissolved to form a blue solution.

Add a dry spatula full of copper sulfate to the other test tube and shake it until the crystals dissolve.

==>A blue precipitate was seen and a colorless and odorless gas was given out. 

Now it comes to the interesting part: Pour the contents of the second test tube into the first test tube!

==> The bluish solution started to fizz!!!

Below is the results of the first test and second test!!!

For the third experiment, we had to place one drop of methylated spirits ( ethanol that has additives to make it poisonous, extremely bad tasting, foul smelling or nauseating, to discourage recreational consumption) onto the back of our hands. We then blew air gently across the back of our hands. It felt very cooling!

For the fourth experiment, I had to quarter fill a very small beaker with lime water. I had to gently blow through a drinking straw into the lime-water. 

==> White Precipitate was formed!

Before Blowing

After Blowing

For the 5th and last experiment, we were to place a few drops of starch suspension in a clean test tube and add a drop of iodine solution. 

==> The iodine solution turned blue-black!

The bottles of stuff we were supposed to use

The results

After that, we were tested on our observation skills! We were supposed to watch a YouTube video and write down as many observations of the burning candle that we could! WE were supposed to use all our candles except for sense of taste (which is obvious, unless we were supposed to lick the candle!! O.o).

Fun Fact: Michael Faraday(1791-1867), a scientist famous for his discoveries in electricity and chemistry, made 53 OBSERVATIONS of a burning candle!!! I only managed 14!

http://www.youtube.com/watch?v=61HlrbxcV9Q

Do try out the activity and see how many observations you can write down!

This is the end of this post! I do hope that you have enjoyed it and I appreciate the time you spent on reading this post!!

Going through Worksheets

Today was a midly interesting lesson, even though the teacher was only going through our worksheet corrections. However, the teacher went through some interesting concepts, and in all, it was a very enriching lesson.

For example, the teacher asked us if we noticed that for every question we had in our Primary School Science that there was a context. For example, in the concept "Photosynthesis", there were many factors affecting Photosynthesis, for example light, carbon dioxide, water. He also told us that in our previous studies, T=ONF.

Besides, the teacher also revised on the laboratory worksheet. Now, I know a lot more things about the Science Laboratory now! Did you know that a pipette can measure up to 1 decimal point and a burette and measure up to 2 decimal points?

Besides that, our teacher also taught us the method of heating alcohol. We could use the water-bath method! Firstly, add alcohol into the test tube. Boil a beaker of water of water with the Bunsen Burner flame. Then switch the flame off and place the test tube which contains the alcohol into the beaker of hot water. That is how to heat a small amount of alcohol safely, as alcohol is a flammable liquid!

Today was a very interesting lesson,but I do look forward to the Science Laboratory lesson where we will be using our test tubes!

Worksheet Lesson...

Sigh...

Today's Science laboratory got replaced by a "Do Worksheet" lesson. Since my Science Teacher was away on a workshop, thus there was a relief teacher called Mr Kiu. However, once we reached the Laboratory, he instructed us to do worksheets 6 and 7, which was like a review of what we had learned. However, the whole class did not have an inkling about the all kinds of funky weird numbers that we were supposed to calculate, as after all, we had not learned about it yet!

However, the teacher was quite friendly and once he realized that we could not answer some questions, he went through the worksheet. Even though the lesson was not that interesting, but we still had some fun as the teacher was very friendly and very interactive with the class.

!Science Laboratory!

Finally! On 15 January, it was my first Science Laboratory lesson and I was very excited and looking forward to it! Mr Tan brought us to the Science Lab and  proceeded to tell us the rules and regulations there. He introduced the various types of Laboratory apparatus to us and taught us how to operate the Bunsen Burner.

Mr Tan tested the whole class individually to make sure that every single one of us knew how to operate the Bunsen Burner. It was quite cool to operate the burner myself, even though I was afraid that I might get burnt by the flame. However, I got bolder after a while and dared myself to open the air-hole of the Bunsen Burner, to allow air to enter the burner.

That day, I learnt about the two types of flames that the Bunsen Burner produces, the non-luminous flame and the luminous flame. I am now able to identify each of the different flames. The luminous flame is unsteadier and more visible compared to the non-luminous flame, which is more often used for heating stuff. In addition, I also learned  about the names of the weird Laboratory apparatus that I would be working with in future.

However, since we were running out of time, we did not get to burn some wooden ice-cream sticks. Although we did not complete the whole activity, I still have a wonderful learning experiences at the Science Laboratory!