This is photosynthesis which is the process of plants getting energy from sunlight. Basically turning sun light and Carbon dioxide in to Oxygen and energy.
Main questions:
What are the four necessary elements for life?
Carbon(C), Oxygen(O), Hydrogen(H), and Nitrogen(N)
What is the space where we found electron and how many percents are there?
90% of electron in Orbital
What is the Molecular Shape?
A molecule’s shape is determined by the positions of its atoms’ valence orbital. Shape is usually the basis for the recognition of one biological molecule by another.
5 main facts:
All chemical reactions are reversible, with the products of the forward reaction becoming the reactants for the reverse reaction.
An element is a substance that cannot be broken down to other substances by chemical reactions. There 92 elements are recognized in this world right now.
A compound is a substance consisting of two or more different elements combined in a fixed ratio.
Mass number is the sum of protons plus neutrons in the nucleus of an atom. The mass number is written as a superscript to the left of an element’s symbol.
Atomic mass is an approximation of the total mass of an atom.
Summary:
Chapter two is basically telling the connection between chemical and Biology. Many lives on earth depend the elements exist on earth to survive. Such as Carbon, Oxygen, Hydrogen, and Nitrogen are the major elements for life. All those elements are form by atoms.
Because we are talking about atoms, that we are involved in the world of atoms. Also the chemical reactions are very important to the world we exist. So if we want to fully understand the nature and everything in this world. Then biology is not the only thing we need to learn but chemistry also.
Key terms:
1. Chemical equilibrium: In a chemical reaction, the state in which the rate of the forward reaction equals the rate of the reverse reaction, so that the relative concentrations of the reactants and products do not change with time.
2. Ionic bond: A chemical bond resulting from the attraction between oppositely charged ions.
3. Isotope: One of several atomic forms of an element, each with the same number of protons but a different number of neutrons, thus differing in atomic mass.
4. Atomic mass: The total mass of an atom, which is the mass in grams of 1 mole of the atom.
5. Atomic number: The number of protons in the nucleus of an atom, unique for each element and designated by a subscript to the left of the elemental symbol.
6. Chemical equilibrium: In a chemical reaction, the state in which the rate of the forward reaction equals the rate of the reverse reaction, so that the relative concentrations of the reactants and products do not change with time.
7. Energy: is defined as the capacity to cause change-for instance, by doing work.
8. Covalent bond: is the sharing of a pair of valence electrons by two atoms.
9. Van der Waals interactions: Weak attractions between molecules or parts of molecules that result from localized charge fluctuations.
10. Chemical bond: An attraction between two atoms, resulting from a sharing of outer-shell electrons or the presence of opposite charges on the atoms. The bonded atoms gain complete outer electron shells.
Video: http://www.youtube.com/watch?v=EBfGcTAJF4o&feature=PlayList&p=32D090BC8084AB76&playnext=1&playnext_from=PL&index=40
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