April Reflections

In this month I went again for another Science for Fun. As always it was interesting with new experiments and so. This month we were introduced to reflection and refraction. At first I was kind of confusing, the convex and concave mirrors, but now I am starting to get it, and how the images come out inverted, or upright, or virtual or real and so on, and now there is refraction to worry about. It is more difficult than reflection because there are different bodies of matter the light rays pass through with different refractive index and so comes out the fake images and the real thing itself. I once mixed up the lines on whether it should be dotted or straight. I need to continue to study this topic to understand more on refraction. Though it is not tested, I still think I should know this topic. And the test is on 5th May which is coming very soon, and I must start to study...

Shao Xuan

(Post #10)

Science Enrichment 2

Different Types of Fertilisers

Fertilisers are very important for the growth of plants. They provide them with nitrogen which gets converted into useful forms either for the plant itself of on the soil for other plants to use. Each plant requires different properties from the fertilisers and so it is very important for farmers to pick the right fertilisers for farming.

Acidic, fertilisers are made up of usually primary and secondary macronutrients. There are 3 primary macronutrients: nitrogen, phosphorous and potassium. The secondary macronutrients are calcium, sulfur and magnesium. One each from two types of macronutrients is usually combined together along with some other micronutrients like boron, chlorine, manganese, iron or zinc.

Rock Phosphate

Rock phosphate, basically PO₃, is actually the 20-million-year-old remnants from the remains of aquatic and land critters. It is in the form of clay, and will not leach out of the soil but be absorbed by roots of the plant. It releases the 30% of phosphorus at a very slow rate and can last for up to 5 years. It is often mixed together with other fertilisers and it can attract roots to the area spread with the fertiliser.

Ammonium Nitrate

Ammonium nitrate is made by combining nitric acid and ammonia. This reaction is very violent though many do not know it. Ammonium nitrate is made up of 27% nitrogen and is usually available in granule form. This is the most popular form of fertiliser because it does not affect the pH of the soil much. It constantly provides a large amount of nitrogen to the plants. However some there are some reservations on this type of fertiliser because it explodes and can be fatal.

Superphosphate

Superphosphate came about from tricalcium phosphate where the latter was too insoluble to form a fertiliser. It is thus reduced to monocalcium phosphate and added to sulfuric acid to form the superphosphate of lime. Superphosphate is usually used in the early stages of gardening. It is very concentrated and should be mixed to other fertilisers because the plants would die if not.

Potassium Chloride/Potassium Sulfate

Also known as the muriate of potash and the sulfate of potash respectively, potassium-based fertilisers are used only when there is a potassium deficiency in the soil. It is applied commonly when sowing. Potassium chloride is the most common potassium-based fertiliser and is also the cheapest. However, if such fertilisers are used in soil where there is an abundance of potassium, it can cause diseases such as root rot. Thus it is applied in small amounts unless there is no potassium in the soil.

Shao Xuan
(Post #9)

Science Enrichment 1

Elements

10 Random Elements

The periodic table is made up of 118 elements so far, but in this list there are 10 random elements picked for reference. Enjoy!!!

1. Chlorine (Symbol “Cl”, Atomic number #17, Atomic mass 35.453)

Uses: Chlorine bombs, organic chlorine compounds, bromine extraction

2. Copper (Symbol “Cu”, Atomic number #29, Atomic mass 63.546)

Uses: Electronics, wires, architecture, alloys

3. Krypton (Symbol “Kr”, Atomic number #36, Atomic mass 83.798)

Uses: Photography, florescent lamps, krypton fluoride laser

4. Iron (Symbol “Fe”, Atomic number #26, Atomic mass 55.845)

Uses: Metal compounds, food and health, blood

5. Gold (Symbol “Au”, Atomic number #79, Atomic mass 196.967)

Uses: Money, jewelry, tooth crowns, electronics

6. Sodium (Symbol “Na”, Atomic number #11, Atomic mass 22.990)

Uses: Alloys, nuclear reactor cooling, transfer heat

7. Aluminium (Symbol “Al”, Atomic number #13, Atomic mass 26.982)

Uses: Packaging, construction, household appliances, alloys

8. Nitrogen (Symbol “N”, Atomic number #7, Atomic mass 14.007)

Uses: Stainless steel, disable explosive liquids, electric parts

9. Cobalt (Symbol “Co”, Atomic number #27, Atomic mass 58.933)

Uses: Alloys, pigments and colourings, batteries

10. Titanium (Symbol “Ti”, Atomic number #22, Atomic mass 47.867)

Uses: Aerospace and marine, architecture, pigment

Shao Xuan
(Post #8)