Wednesday, 2 July 2014

Vernier Caliper, Micrometer Screw Gauge and Zero Error

On 18 February, it was one of those dull worksheet lessons in which we stayed in class to do worksheets. So, on that day,Mr Tan taught us how to use the
vernier caliper, and the micrometer screw gauge. In addition to that, before the lesson, we had attended an IVLE lesson in which it had also taught us on how to use the Vernier Caliper and the Micrometer Screw Gauge. Besides, we learnt about Zero Error, in which it means that the measuring instrument still has other measurements other than 0 when it is fully shut.

On 26 February, I managed to apply this knowledge of usage of vernier calipers and micrometer screw gauge. However, besides that, I also learnt the difference between Raw Data and Processed Data.

Raw Data are measurements taken directly from a measuring instrument. This is expressed to a fixed number of decimal places dictated by the units used and the precision of the instrument.

Processed Data  are readings obtained from the calculations of one or more sets of raw data.

So, now back to what we did. We first measured the height of a seat using a metre ruler. Next, we measured the internal and external diameter of a beaker with a vernier caliper. Besides that, we also measure the diameter of a wire and a marble using the micrometer screw gauge.

All together, I learned how to use the vernier caliper and micrometer screw gauge. Besides that, i also ensured that the vernier caliper and micrometer screw gauge had no zero error at all!

Vernier caliper


                                                                 
                                                 Micrometer screw gauge

Tuesday, 1 July 2014

Kinetic Particle Theory, Brownian Motion and Diffusion

On 1 April 2014, the teacher taught us about the Kinetic Particle Theory, Brownian Motion and Diffusion.

So, What is the Kinetic Particle Theory? The Kinetic Particle Theory is a theory that states that matter is made up of large number of tiny particles (atoms or molecules), which are a continuous and random motion.

Besides, we also learnt about Brownian Motion! Brownian Motion is the continuous and random motion of small particles in fluids (liquids or gases). Brownian Motion involves 2 motions, a gas/liquid particle that is the particle that is moving continuously and randomly due to its kinetic energy. The other type of motion would be small solid particles that are bombarded by the gas particles in random directions, therefore causing it to move.

In addition, we learnt that Diffusion is the particles moving randomly from a region of a high concentration to lower concentration.




Monday, 30 June 2014

Significant Figures and Decimal Points

On 12 February 2014, my Science teacher taught us about significant figures and decimal points!

Regarding the topic of significant figures, there are a few rules regarding significant figures.

Firstly, Non-zero digits are always significant.

Secondly, All final zeros after the decimal point are significant.

Thirdly, Zeros between two other significant digits are always significant.

Fourthly, Zeros used for only spacing the decimal are not significant.

Besides, I  also learnt about the Calculation of Physical Data. I also did learn some news stuff to expand my knowledge!

For example, for Addition and Subtraction, The final value has the same number of decimal place / same place value as the least precise measurement.

For Multiplication and Division, The product / quotient has the same number of significant figures as the number with the least number of significant figures.

For Average, The final value has the same number of decimal place / same place value as the least precise measurement.

Meanwhile, for Constant, The number of decimal place / place value of a constant is not considered in a calculation.

In addition to this, I also learned about the accuracy of devices, the smallest division and the amount of uncertainty that each apparatus had!





Monday, 12 May 2014

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!

 Lastly, we also learned about unit conversion. 
 

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.

Sunday, 16 February 2014

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!


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!!