Lecture-2-Chemistry-_42283

Lecture-2-Chemistry-_42283 - Liketheabiotic world,...

Info iconThis preview shows pages 1–6. Sign up to view the full content.

View Full Document Right Arrow Icon
The Chemical Nature of Life •L i k e the abiotic world, living organisms are a collection of atoms (representing different elements ) that are linked by chemical bonds to form molecules . • Unique to life, are the myriad of molecules primarily comprised of one or more of these four elements: carbon, ydrogen oxygen & nitrogen of hydrogen, oxygen & nitrogen comprise 96% of body weight 4%: Ca, K, S, Na, P, Mg, Cl atomic number element % of Human body wt. Trace elements (0.01%): I, Fe, Co, Zn, B, Mn, Se, Emergent properties : atoms molecules, example: H O H properties of 2H + O 2 2 O ; properties of elements O , H vs. that of water.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
ATOMS Atomic Structure 01 HAVE SUBATOMIC PARTICLES 101 a. d. g. determine located in: combine to get located in b. atomic number e. h. shells constant for each may differ in various outer shell called c. f. isotopes i.
Background image of page 2
Atomic Structure he element helium lectrons: ( charge; atomic number The element helium Isotopes of an atom: different number of eutrons (proton & electrons: (–) charge; # electrons = # protons neutrons (proton & electron quantity identical) nucleus of: protons: (+) charge & neutrons (uncharged) –a l l exhibit same chemical properties d ii t tb l atomic mass Radioisotopes : unstable nuclei, decay giving off energy/matter. gy/ –c an be detected; use as tracers to follow molecules biological reactions Elements are neutral : # electrons = # protons tomic number = # of protons in biological reactions. Also, many applications in medicine. Atomic number # of protons Atomic mass = # of protons + # of neutrons
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Electrons Have Potential Energy • Potential energy: energy due to the arrangement or position of matter –An electron’s potential energy is proportional to its’ distance from the ucleus; determined by which energy level or shell the electrons nucleus; determined by which energy level or shell the electrons occupy Energy absorbed by an atom n result in electrons can result in electrons moving to higher levels (shells), or even out of the atom altogether. EX: Photosynthesis Electron transfers between molecules = transfers of nergy ese rocesses energy; these processes fuel metabolism.
Background image of page 4
Distribution of Electrons in an Atom Electrons are in constant motion around the nucleus; occupy regions called orbitals , and these occur in discrete layers around the nucleus, termed shells . rbitals n hold a maximum of 2 e Orbitals can hold a maximum of 2 e –Th e quantity of energy levels, or shells, is determined by the quantity of electrons: 1st shell: 1 orbital only (2 e ’s max) 1s 2nd shell: 4 orbitals (8 e ’s max) 2s, 2px, 2py, 2pz 3rd shell: 4 orbitals (8 e ’s max) **note that an atom has 3 Neon; atomic 2e 8e Is neon a a 3 D shape number 10 10e total 1 st shell 2nd shell reactive molecule?
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 6
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

Page1 / 18

Lecture-2-Chemistry-_42283 - Liketheabiotic world,...

This preview shows document pages 1 - 6. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online