chem - Review Sig figs places Atomic number number of...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon

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

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

Unformatted text preview: Review Sig figs places. Atomic number : number of protons in the nucleus Empirical formula : reduced Temperature heat : energy transferred due to temperature differences Molar mass : the mass, in grams, of one mole of an element. Measured in amu or Daltons, both of which equal g/mol. The nucleus stays together because the strong nuclear force overcomes the Coulombic repulsive force at small distances. The electrons don’t fall into the nucleus because: a) Quantization of energy is such that electrons can’t lose just enough energy to collapse into the b) An electron at rest in the nucleus would violate the Heisenberg Uncertainty Principle: you would know its position and velocity at the same time. (The line-emission spectrum is the spectrum emitted when an electron returns from its excited state to its ground state. You can only get certain colors because electrons can only "fall" certain amounts, and the amount of electrostatic potential they lose is proportional to the color of light that is emitted. Pinpointing an Electron: The Four Quantum Numbers n, the principal quantum number , describes energy level. l, the azimuthal or angular momentum quantum number , describes orbital. (0=s, 1=p, 2=d, 3= f, 4=g, etc.) m l , the magnetic quantum number , describes direction in space (e.g. p x , p y , p z ). m s , the spin quantum number , can be either 1 2 and describes the orientation of the electron’s magnetic field relative to an outside magnetic field. Principles of Orbitals The Aufbau principle Hund’s (bathroom) Rule (fill orbitals one at a time, then double up) The Pauli Exclusion Principle (only two electrons can occupy each orbital, and they must have opposite spins) Solubility Rules 1. Salts containing Group I elements are generally soluble. Salts containing the ammonium ion, nitrate ion, perchlorate ( ClO 4 ) ion, or acetate ion are soluble. Exceptions to Rule 1 are rare. 2. Halide salts besides silver (I), lead, and mercury halide salts are generally soluble. Sulfates are generally soluble, with the exceptions of (Ba, Sr, Pb (2+), Hg (2+)) sulfates. 3. Hydroxides, carbonates, sulfides, and phosphates are generally in soluble. Strengths of Acids and Bases A strong acid or base is one that dissociates completely in aqueous solution. Weak acids/bases don’t dissociate completely. Examples of strong acids include perchloric acid, sulfuric acid (first dissociation in solution only . H 2 SO 4 is a diprotic acid, meaning it can dissociate in two separate, consecutive reactions in dissociates. The second dissociation (removal of the second hydrogen) is only intermediate.), hydrochloric acid, hydrobromic acid, hydroiodic acid, nitric acid, and the hydronium ion....
View Full Document

This note was uploaded on 04/14/2008 for the course CHEM 211 taught by Professor Smucker during the Fall '07 term at Austin College.

Page1 / 10

chem - Review Sig figs places Atomic number number of...

This preview shows document pages 1 - 3. Sign up to view the full document.

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