The Swedish Chef tells you that students from his baking class today each had specific roles in helping out with lunchtime food preparation: Fiona was in charge of measuring the flour Scott measured out the salt Brenda looked after the baking soda Isaac was dusting some donuts with icing sugar Chris was sitting off to the side with a sore throat eating throat lozenges that contained citric acid. Can you help him figure out who may have committed the crime? Purpose Question "How can some physical properties of solids be used to identify the solids as lonic or molecular compounds?" Prelab Thinking There are some characteristic physical properties that are unique to most lonic and most molecular compounds. Create a table like the one below and fill in the blanks using any resources you wish. Characteristics ionic compound molecular compound Type of element/ particle present.. lons (metal ion +non metal lon) elements How bond form... By permanent transfer of valence electron of one By mutual sharing of electron between the two atoms atom to another. (forms ionic (forms covalent bond) bond) text Calibri 11 + BI U A 15 E 1 23 4 567 110 12 13 14 15 16 Force... electrostatic force of attraction Vander waal's force of attraction IUPAC naming rule name the cation first(a metal), then anion ( a non metal) and suffix the anion to "ide" Ex: NaF (Sodium flouride) electropositive element should be named first name sec3 element add suffix "ide" to it. Add prefix mono di tri to refer to number of atoms. Vowels should not be repeated. Ex PCI, (Phosphorus trichloride) At room temperature solid they are mostly gases, liquids. and solid Physical property soft Hardness Usually hard low mp quite high Solubility in water highly soluble it varies Conductivity Good poor low Boiling point very high Lab Design 1. Write a procedure (1.e. like a series of step in a recipe) that you would follow to test what you believe to be the three most important, testable physical properties of the 5 white powders involved in this crime (flour, salt, baking soda, icing sugar, citric acid) to determine if they are lonic or molecular. Imagine that you have access to any of the equipment in a typical science classroom. 2. Design an empty observation table that you would use to collect the necessary data during your procedure. Analysis 1. Discuss in detail how you could use the information collected in your lab to determine if the powder in the white footprints is lonic or molecular. Furthermore, how could you use this information to determine who might have committed the crime? 2. Explain how you decided which three physical properties to test
