Chapter 2

Chapter 2 - Chapter 2: Atoms, Molecules, and Life...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Chapter 2: Atoms, Molecules, and Life Understanding chemistry is important because interaction between atoms is one of lowest levels of biological organisms ? Atom = smallest unit of organisms o basic unit of all forms of matter o smallest unit that retains physical and chemical properties of element o made up of neutrons, protons, electrons (fig 2.1) protons = (+) particles at nucleus of atom neutrons = uncharged particles at nucleus of atom electrons = (-), light, orbit nucleus in electron shells collection of atoms of same type form elements o can’t be broken down into other substances by chemical reactions O, C, H, N are the 4 most common elements in living organisms Atomic weight = # of protons (+) and # of neutrons o The atoms of a particular element may have different number of neutrons Results in isotopes Different atomic weights o The electron orbitals 3D space around the nucleus of an atom where an electron will be found 90% of the time the electron orbitals of an atom are arranged in electron shells based on their energy level only care about outer level, trying to fill it up, determines reactivity and bondness atom with incomplete electron shell is reactive full electron shell is inert (not reactive) ? an inert element = has full outer electron shell o hindenburg = 1937 = hydrogen, reactive, combustible
Background image of page 1

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

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 12/01/2010 for the course BIOL 1001 taught by Professor Minor during the Fall '08 term at LSU.

Page1 / 3

Chapter 2 - Chapter 2: Atoms, Molecules, and Life...

This preview shows document pages 1 - 2. Sign up to view the full document.

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