Determination of an Empirical Formula, Slides of Chemistry

Download Determination of an Empirical Formula and more Slides Chemistry in PDF only on Docsity! Determination of an Empirical Formula Created by Schweitzer 9/30/04 Objective CuIx  Determine the Formula between Copper and Iodine when combined in the presence of a flame.  Different Oxidation states may form depending on conditions  Copper (I) Iodide CuI  Copper (II) Iodide CuI2 Data Collected  Mass of Clean strip of Copper  Mass of Copper strip with CuIx  Mass of Copper Without CuIx  What do we need to get from this data? How do we get the Mass of the Iodine? 1. Mass of Clean strip of Copper 2. Mass of Copper strip with CuIx 3. Mass of Copper Without CuIx  The only difference between the 1st and 2nd masses is the iodine that reacted Mass of Iodine How do we get the Mass of the Copper? 1. Mass of Clean strip of Copper 2. Mass of Copper strip with CuIx 3. Mass of Copper Without CuIx  The only difference between the 1st and 3nd masses is the copper that reacted Mass of copper Error analysis  You hastily over heated your Copper strip producing a cool green flame.  How will this affect your result? Error analysis  Over heating will cause CuO to form. Or additional Oxygen will be added to your Copper strip.  This appears as additional Iodine.   Less copper more iodine Cu:I Error analysis  While you were cleaning the CuIx off of the copper strip you over cleaned and removed considerable unrelated copper Descriptive chemistry •What is the purple stuff? •Iodine (I2) is easily converted to I2 vapor with a little heat. •I2 vapor is the purple stuff Descriptive Chemistry What is the pale white substance??? Note the Sample on the right contains some Black stuff????