3. Solutions Dissolve as Individual particles Molecular Substances Dissolve as Molecules Molecular Substances Are composed Of non-metals
4. Ionic substances Are composed of Ions Often a metal + non-metal Or poly atomic ion NaCl Na2SO4 Dissolve as individual ions Electrolytes Recurrent theme!!!
9. Physical properties Observed without converting to another substance Intensive – characteristic of the substance Extensive – depends on amount of substance present (mass and volume most important!) Change of state – physical change – no change in Composition – ice liquid water water vapor – still H2O Other examples: hardness, mp bp, solubility, density, viscosity, color, taste, Smell (senses) –intensive
11. Chemical properties describe how it can change into other substances In a chemical change – atoms rearrange to form new substances with new chem/phy properties What does it react with O2, acids, bases, oxidizers, reducers Does it rust, tarnish or combust?
16. SEPARATIONS Using differences in physical properties to separate pure substances in mixtures Bp, mp, solubility, magnetism Pasteur – crystal separation
20. Aug ’07 news article Cat in nursing home Curled up with dying Patients – How did it know? Metabolites in breath May be used to help Diagnose internal Infections/cancers!! What common breath test is frequently used? What condition can a nurse diagnose by smell of breath?
22. Temperature Temperature – degree of hotness or coldness! Intensity of energy Heat – energy – depends on Temperature Mass Type of substance Equal masses of water and oil on similar burners, similar time – temp??
23. Temperature scales What scales are you familiar with How many degrees between fp and bp water in oF…. oC 2 patients are sick A) 1o F fever B) 1o C fever Which is sicker???
24. Fever Why?? Infection fevers Are not likely to Cause “heat stroke “Heat stroke” Overheating Core body temps Fevers: adults vs Infants…
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26. practice Sig fig – ans should have same number of decimal places!!!