081a.Matter&Elements.doc1 of 1
01/23/14
Resources:Table salt & sea salt
New & old pennies / balances (2)
Penny pieces / spot plate / web cam / HCl
Homework: Read 38-44 / Q 1, 2, 3, 5, 6, 8 p60
Bell Work:Hand out TOE & PT
- Matter reprise (take notes now)
- Matter isn’t energy (except that it is)
- Matter has mass
- Matter made of atoms
- Kinds of Matter
- Pure Substances: single substance with “definite properties” (always the same)
- Mixtures: combination of substances with indefinite properties
- Example:
- ALL pure salt (sodium chloride) tastes the same, dissolves the same and boils and melts the same
- “Sea Salt” is random combination of sodium chloride and whatever else is dissolved in the ocean — so different sea salts taste different, etc
- Demo: taste test table salt versus sea salt
- “PURE” sea salt isn’t PURE! (in the chemical sense)
- Only two kinds of pure substances: elements & compounds
- Elements: Relatively rare – but known to the ancients as special materials (like gold & silver)
- Substance with all one kind of atom
- Atoms are smallest building blocks of ordinary matter
- Atoms have nucleus with Ps and Ns, with cloud of Es outside (sketch reminder)
- Atoms in nature come in 88 “flavors” depending on number of protons
- Atomic “Menu”: Periodic Table
1)Hand out Periodic Tables
2)Have S pick number 1-100 and find that element on PT, explaining that “atomic number” = number of protons (refer to Key) and emphasizing that ALL ATOMS of that element have SAME number of protons!
3)Updates – see PT.updates.ppt (Copernicium, Flerovium, Livermorium, Ununseptium)
- Therefore, element cannot be broken down into simpler substances (with chemical means) — one type of atom is as simple as it gets! Purest of the pure!
- Each element has its own definite (always the same) chemical and physical properties — Penny Example
- Physical: Weigh 10 old & new pennies
- Chemical: add HCL to piece of new and old penny on spot plate or small tt
- Zinc (find on PT) is less dense than copper (find on PT) and reacts with HCl — which penny is made of zinc?
- ADOPT-AN-ATOM:
- Every student finds an element that they recognize or has an interesting name
- Write down and box in notebook – you’ll be using these later!
- Write down how many protons your element has (ask for examples)
- Chicken-and-Egg Problem: If elements are simplest building blocks, where did they come from?
- Hydrogen, helium and (a little) lithium from BB
- Other elements up through Fe made inside stars
- Everything else from supernovae