BIOL 101 1st Edition Lecture 2Outline of Last Lecture I. Matter, elements and the structure of the atom.Outline of Current Lecture II. Isotopes A. RadioactiveB. Non-radioactive (heavy)C. Use in Biological ResearchIII. Electron Energy, Distribution and Chemical PropertiesA. Energy Correlated with Electron Shell B.Valence Electrons and Reactivity IV. Chemical BondsA. CovalentB. Ionic BondsC. Weak Chemical BondsV. Chemical ReactionsCurrent LectureI. Isotopes are identified or tracked by the number of neutrons they contain. Carbon-15 has 15 isotopes. There are two types of isotopes, radioactive and non-radioactive. A. Radioactive isotopes are non-stable, meaning that they disintegrate over time. The disintegration of the isotope produces particles. Ex: Carbon has a half-life of 5,700 years. So after 5,700 years have gone by, half the isotope will be disintegrated. Half-life and energy are inversely related.i. Hydrogen typically only has one proton and no neutrons. For the purposes of biological research, scientists can form hydrogen with a neutron, which forms hydrogen into a radioactive isotope. B. Non-radioactive isotopes are also referred to as heavy isotopes. These types of isotopes do not disintegrate over time are relatively stable. “Heavy H2O” is a non-radioactive isotope used in biological research for testing nuclear material. When These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.isotopes are used for biological research it is extremely important to understand half-livesas well as the amount of energy released from the particles. II. Electron Energy, Distribution and Chemical Properties are all important concepts to understand when learning about the chemical properties of the atom. Each atom contains 8 potential spots for electrons to orbit their nucleus. Once all 8 spots on the electron cell are filled, the atom has reached valence. Valence is important because is it the most stable state,meaning it does not react with other things. Atoms are always striving towards valence. A. Valence is achieved through the transfer and gain of valence electrons and through chemical bonds.III. There are multiples types of chemical bonds. A chemical bond is an attraction of two or more atoms. A. Covalent bonds are possible through the sharing of electrons between two atoms. This is a very strong bond. When two atoms have an equal sharing of electrons then they have formed a non-polar covalent bond. A polar covalent bond occurs when there is an unequal sharing of electrons therefore the cells have different polarities. B. Ionic bonds are identified through the transfer of electrons. At any given time in an ionic bond, there is an atom that has lost an electron (becomes more positive- remember because electrons are negatively charged) and an atom that has gained and electron (becomes more negative). The atom that looses the electron is known as the cation- a positively charged ion, and the atom that gains the electron is known as an anion- a negatively charged ion. This chemical bond is possible because of the rule “opposites attract.” This bond is not the strongest bond. C. Hydrogen bonds and Van Deer Waals bonds are considered weak chemical