9/29 OBJECTIVES (from yesterday): Atoms! (Week 5) 9/29 OBJECTIVES (from yesterday): 1. Define and distinguish atom, element, molecule, compound, and matter. TASK: What is an atom? Please write your answer in a complete sentence or two. (on notes)
About That Test… Mean: ~80 Range: 43-100 Corrections: Thursday is best. Next Tuesday also good.
Biochemistry My Favorite! Super-cool introductory video
Atoms are small An atom is the smallest piece of an element that is stable under normal conditions. All matter is made up of atoms
(almost) Everything is made of atoms! Sugar
Even You and Every Other Living Thing are Made up of Atoms. Matter: anything that has mass and takes up space. Keratin is a protein that is made of matter. Everything except energy is made up of matter
How small? …and 1 cell is made up of about 100,000,000,000,000 atoms 1 human is made up of about 100,000,000,000,000 cells!
Atoms are Ridiculously Small A MILLION atoms in a straight line would be as thick as a single human hair!!! The radius of a carbon atom is only 0.22 nm
Good thing Science has Powerful Microscopes! Each bright spot is a single atom
Elements: substances made up of only 1 type of atoms An element is a substance made up of only 1 type of atom. Only silver atoms in here!
Water is a compound made of oxygen and hydrogen atoms. Compounds Compounds are pure substances made of more than one type of atom, joined together Water is a compound made of oxygen and hydrogen atoms.
Different Elements = Different Atoms Atoms of different elements are different from one another because they have different numbers of protons, neutrons, and electrons.
Molecules A molecule is the smallest piece of a compound. Wally the Water Molecule says: “If I get broken down any farther, I won’t be water anymore… I’d just be a mixture of hydrogen and oxygen!” Wally
Parts of an atom: Label the diagram Atoms contain 2 parts: The atomic nucleus contains protons and neutrons Electrons fly around the nucleus near the speed of light
Atom’s radius = 170 pm Nucleus’ radius = 0 Atom’s radius = 170 pm Nucleus’ radius = 0.0027 pm 105 = 5 orders of magnitude. Fruit Fly length = 0.002 m Camden Yard’s radius = 150 m 105 = 5 orders of magnitude.
Atoms Atoms are made of three particles: Protons Neutrons Electrons Positive Charge In Nucleus Neutrons No Charge Electrons Negative Charge Outside of Nucleus in Electron Cloud Have Negligible (zero) Mass
Wait…Electron Cloud?
Electrons are seemingly everywhere at once! We cannot pinpoint electrons to one given spot at one given moment – they move too fast They are PROBABLY found in various energy levels around the outside of the nucleus:
We’ll Deal more With Electrons Tomorrow… For now, EXIT TICKET!