In this practical, we learnt about the different apparatus in the science lab. This is a very important as it is the basics that one would need in order to do experiments. For example if the experiment requires one to use a evaporating dish, we would need to know which one is the correct equipment or else the experiment cannot work. From this practical, I learnt something new that I had not learnt before in Primary School. They are the use of the burette, pipette, thistle funnel etc.
1P2- Bunsen Burner
This practical is about the usage of the Bunsen Burner.
We learnt how to light a Bunsen Burner.
The steps:
1) Check that the Bunsen Burner is not damaged
2) Ensure that the air hole is closed
3) Open the gas tap
4) Ignite the lighter just above the barrel
5) Open the air-hole slightly
We also learnt how to prevent a strike back from happening.
1P3- Types of Flames
1P4- Observations and Recording
This practical teaches us how to observe and record down information.
Observing is important as it helps us analyze and understand something or someone.
One of the important things I learnt is that instead of saying limewater will turn milky or chalky, it is called white precipitate. 1P5- Part 2
This practical teaches us how to boil substances safely and how to record accurately.
In question 8(i), i accidentally spelt temperature without the 'ure'
Oops :D
Recording is important as if we do not record down the results, there is no point of carrying out the experiment unless one has a very very very very very very excellent memory( doubt anyone has)
1P6- Measurement of Length (experiment)
In this experiment, we learnt on how to measure length using the vernier calipers and micrometer screw gauge.
Most of the answers I had answered wrongly because i did not put in to the nearest 1 decimal place.
the micrometer can measure starting from the smallest 0.01mm.
the vernier calipers can measure starting from the smallest 0.01cm.A ruler that has the highest reading of 1m is called a metre rule.
1P7- Measurement of Time- Pendulum(experiment)
In this experiment, we are supposed to swing a pendulum and record the time it takes to complete 1 oscillation. It was funny when the calss called the pendulum bob, 'Bob', and trying to 'kill' it. :D.
We learnt how to plot a graph too.
The experiment was overall successful.
1P8- Density of Regular Solid
Nothing interesting in this practical, quite boring. :D
But I learnt some formulae such as the calculating density and volume of sphere.
1P9- Density of a regular solid
This practical is very similar to the one before. Nothing much here either,
1P10-Brownian Motion
We did not do this experiment. But from this practical, I understand more about Brownian motion.
Brownian motion is the movement of air particles or solid particles moving in a random direction. It need not be liquid, it can be talcum powder or pollen grains in water. The air particles bombard unevenly on all sides of the particles thus it move randomly and continuously. If the temperature increases, the particles will move faster.
1P11- Investing mixture and compound
In this practical we did 2 experiments. The first one is on mixture of iron and sulfur. From this, I had learnt that sulfur should be spelt sulfur instead of 'sulphur'. The colour of sulfur is yellowish but the colour of iron powder is reddish-brown. However after you combine those two powders together using chemical methods, a black powder is formed.
Compounds
1. Compounds are pure substances.
2. They are made up of two or more elements combined chemically.
3. The constituents of a compound are present in a fixed ratio.
4. Compounds have fixed properties. For example, a particular compound will have fixed temperatures at which it melts and boils.
5. A compound can have properties different from its constituents, as a new substance is formed when the constituents are chemically combined.
6. The constituents of a compound can be separated only by chemical methods.
Mixtures
1. Mixtures are impure substances.
2. They are made up of two or more substances mixed physically.
3. The constituents of a mixture are present in varying ratios.
4. Mixtures do not have fixed properties. Their properties depend on the nature of their components and the ratios in which they are combined.
5. In mixtures, no new substance is formed. The properties of a mixture are the same as the properties of its constituents.
6. The constituents of a mixture can be separated easily by physical methods.
(the above are the differences in mixture and compound)
1P12- Forming Compounds
This experiment is rather interesting as the interesting reaction when the two elements combine. It is a quite magnificent scene.The first part of the experiment is on burning the magnesium strip. My lab partner, Aaron, i don't know why, but never wants to turn on the Bunsen Burner himself. After the magnesium strip was burnt, a white dazzling light was formed. This was the chemical reaction between the magnesium and the oxygen in the air used for burning. The ashes which are formed is white and powder-like is called magnesium oxide.
2 Mg(s) + 1 O2(g) ---> 2 MgO(s)
OR
Magnesium + oxygen ---> Magnesium Oxide
The 2nd part is more interesting. It is to react iron with sulfuric acid. After which, effervescence is formed, the effect is rather cool
The third part is on reacting lead(ll)nitrate and sodium chloride. After which white precipitate is formed, creating the 'fizzing' effect. :D
2 NaCl + Pb(NO3)2 --> PbCI2+ 2 NaNO3
OR
Lead(II) nitrate + sodium chloride -------> lead (II) chloride +sodium nitrate
We also reviewed on the differences between metals and non-metals.
Metals
========================
malleable; can be shaped easily.
Readily conduct heat.
conduct electricity.
High melting points.
Non-Metals
=========================
Brittle.
Do not easily conduct heat.
excellent insulators of electricity.low melting points.
========================
malleable; can be shaped easily.
Readily conduct heat.
conduct electricity.
High melting points.
Non-Metals
=========================
Brittle.
Do not easily conduct heat.
excellent insulators of electricity.low melting points.
1P13- Which can Dissolve more?
This experiment is to test which substance has a higher solubility rate. The three substances are baking soda, iodine crystals and salt. The experiment is concluded with the results of salt having the highest solubility rate followed by baking soda and iodine crystals being the least.
1P14 and 1P15- Separating techniques
This experiment is to separate salt and sand. The way to separate it is to mix both into water then stir it well then filter it. Only salt will be dissolved in the water therefore the filtrate only contains salt. After which, we heat the solution leaving only salt in the evaporating dish. For 1P15, we use chromatography to separate ink
1P14 and 1P15- Separating techniques
This experiment is to separate salt and sand. The way to separate it is to mix both into water then stir it well then filter it. Only salt will be dissolved in the water therefore the filtrate only contains salt. After which, we heat the solution leaving only salt in the evaporating dish. For 1P15, we use chromatography to separate ink
1P16- Inside of cells
This experiment is to observe a onion skin cell and a cheek cell. I had to scrape my cheek cell as my lab partner refused to. We did manage to see the cheek cell but did not manage to see the plant cell as clearly.
1P17- Moving waters
This experiment was quite interesting, although it was done by the teacher. In this experiment, we had to see that the water rises up the visking tubing. Although it was a quite long, it was fruitful as we got to see the amazing result.
1P18- Bouncy Raw Egg
We had to put a quail's egg in dilute hydrochloric acid. The effect is quite cool when we see that bubbles of gas were emitting from the egg and soon the egg's shell was broken off entirely. Our egg's shell broke off very fast compared to other people. But in the end it grew mould over the week and therefore need to be thrown away. Quite sad not being able to see the results.
1P19- I did this experiment in Primary School before therefore i know much about it. But it was quite fun to see the colour of the leaf change to the dark blue and yellowish brown.
