2a2 Science Blog: Feb 9, 2011

A harmful compound(By Kenneth Neoh)

Harmful compound sulfur dioxide (SO4)

Harmless constituent elements: Oxygen(O) and Sulfur(S)

Why is it harmful: Breathing in this gas might cause breathing problems and respiratory diseases. Might also cause premature death.

Chemical Bonding: Covalent Bonding

Constituent elements:

Sulfur: Atomic number 16, a non-metallic element that is yellow in colour. It is essential for life and found in 2 amino acids, cysteine and methiodine. Used mostly as fetilizers if not gunpowder pesticides etc.

Oxygen:Atomic number 8, non-metallic gas which is found colourless in gaseous state and pale blue in liquid state. It consists of 20.8% of the atmosphere in earth and is highly reactive, thus making it form compounds with almost any other element readily.

Sulfur dioxide: Formed by burning sulfur, which is bonding oxygen with sulfur through covalent bonding.

Dot and cross diagram:

Pleasant reminder...

The admin have noticed that Jason had used Wen Yangs account to do his posting. This is TOTALLY unacceptable. Jason, save your work on a word document, and post it using YOUR OWN account. Thanks. Also, the admin would like to remind 2A2 to hand in their work puntually by Valentines day.

The Admin

Carbon monoxide (ethan's work)

Carbon monoxide:

Carbon monoxide is a harmful compound which consists of two harmless elements. The two harmless elements are carbon and oxygen so that is why Carbon monoxide's symbol is "CO".

Constituent elements:
Carbon--- it is nonmetallic and tetravalent which makes four electrons available to form covalent chemical bonds. Carbon, in all forms, are very stable and this is why it requires high temperature to react with oxygen to form CO. It is the 15th most abundant element in the earth's crust and is present in all lifeforms like human bodies.

Oxygen---it is a member of the chalcogen group on the periodic table and is highly reactive which readily forms compounds with almost all other elements in the periodic table. Oxygen, is also colorless, odorless and tasteless and is needed for living things to survive. It is the third most abundant element in the earth's crust and was discovered in 1773 or earlier.

Formation:
Carbon and oxygen is connected by a triple bond. This bond consists of two covalent bonds and one dative covalent bond. Covalent bond is a form of chemical bonding where elements share electrons between each other. Carbon has 4 electrons while oxygen has only 6 electrons. This shows that they do not have a full outer valence shell so they have to share electrons. In the end, after the two elements share electrons and have full valence shells making the element stable and forming a new compound.

Dot and cross diagram: LOOK ABOVE

Sources:
http://en.wikipedia.org/wiki/Carbon_monoxide
http://sixthsense.osfc.ac.uk/chemistry/bonding/covalent.asp
http://en.wikipedia.org/wiki/Oxygen
http://en.wikipedia.org/wiki/Carbon
Google

Done by: Ethan Teo (12) 2a2

The harmful compound that I identified is carbon monoxide. It is formed by covalent bonding.
Carbon monoxide is produced from the partial oxidation of carbon-containing compounds; it forms when there is not enough oxygen to produce carbon dioxide (CO2), such as when operating a stove or an internal combustion engine in an enclosed space.Carbon monoxide is produced from the partial oxidation of carbon-containing compounds; it forms when there is not enough oxygen to produce carbon dioxide (CO2), such as when operating a stove or an internal combustion engine in an enclosed space.
Carbon is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds.Oxygen is a member of the chalcogen group on the periodic table, and is a highly reactive nonmetallic element that readily forms compounds (notably oxides) with almost all other elements.

http://wiki.answers.com/Q/How_is_carbon_monoxide_formed_and_what_is_it_used_for

http://en.wikipedia.org/wiki/Carbon_monoxide

Jason's Work...

WRITE UP ON A DANGEROUS COMPUND

Carbon monoxide (CO), also called carbonous oxide, is a colorless, odorless and tasteless gas which is slightly lighter than air. It is highly toxic to humans and animals in higher quantities, although it is also produced in normal animal metabolism in low quantities, and is thought to have some normal biological functions. It consists of one carbon atom and one oxygen atom, connected by a triple bond which consists of two covalent bonds as well as one dative covalent bond.

Covalent bonding is a form of chemical bonding that is characterized by the sharing of pairs of electrons between atoms, and other covalent bonds. In short, the stable balance of attractive and repulsive forces between atoms when they share electrons is known as covalent bonding.
Carbon is the chemical element with symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds. There are three naturally occurring isotopes, with 12C and 13C being stable, while 14C is radioactive, decaying with a half-life of about 5730 years. Carbon is one of the few elements known since antiquity. The name "carbon" comes from Latin carbo, coal.
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots (acid, literally "sharp", referring to the sour taste of acids) , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition. At standard temperature and pressure, two atoms of the element bind to form dioxide, a colorless, odorless, tasteless diatomic gas with the formula O2. It is a highly reactive nonmetallic element that readily forms compounds with almost all other elements.

Bibliography:
• http://en.wikipedia.org/wiki/Oxygen
• http://en.wikipedia.org/wiki/Carbon_monoxide
• http://en.wikipedia.org/wiki/Carbon
• http://upload.wikimedia.org/wikipedia/commons/6/65/Carbon-dioxide-octet-dot-cross-2D.png

Harmful Compound formed by two harmless elements

Harmful Compound: Methane (CH4)
Constituent Elements: Carbon (C) and Hydrogen (H)

Methane
-A potentially dangerous gas as an asphyxiant
-An explosive compound
-A greenhouse gas

Formation of Methane and its constituent elements
Methane is a highly explosive compound when it reacts with other gases such as oxygen. It is formed by covalent bonding, with the electrons of 1 carbon atom, sharing with 4 other hydrogen atoms' electrons, to form methane, to ensure that both elements have a complete outer shell and are stable.

It is formed by carbon, a non-metallic and tetravalent element with 4 electrons available for covalent bonding, and hydrogen, a non-metallic abundant gas in the Earth's atmosphere with 1 electron available for covalent bonding. When 4 hydrogen atoms react with 1 carbon atom, they would share their electrons to form methane.

Methane is formed through an abiogenic processes. Extremely deep under the earth's crust, there exist hydrogen-rich gases and carbon molecules. As these gases gradually rise towards the surface of the earth, they may interact with minerals that also exist underground, in the absence of oxygen. This interaction may result in a reaction, forming elements and compounds that are found in the atmosphere (including nitrogen, oxygen, carbon dioxide, argon, and water). If these gases are under very high pressure as they move toward the surface of the earth, they are likely to form methane deposits, similar to thermogenic methane.

Methane can also be formed through methanogens, tiny methane-producing micro-organisms, chemically break down organic matter to produced methane. These micro-organisms are commonly found in areas near the surface of the earth that are void of oxygen.

Dot and Cross Diagram of Methane: