Slide 1

Solubility and Properties of Water Section 2.3 Properties of Ionic and Molecular Compounds

Slide 2

Objectives Classify ionic and molecular compounds based on their properties Use a solubility chart to predict whether an ionic compound is soluble in water Relate the molecular structure of water to its properties

Slide 3

Solubility Solubility: the ability to dissolve (in our case, in water) Aqueous (aq) : when something is very soluble Solid (s) : when something is slightly soluble/doesnt dissolve well Decide this by using a solubility table: page 57 in textbook and on your data sheet

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Demonstration Copy the following table into your notes and fill in during the demonstration: silver nitrate strontium nitrate sodium iodide sodium sulfate barium iodide silver nitrate strontium nitrate sodium iodide sodium sulfate barium iodide

Slide 5

How to use a solubility table page 57 in textbook and on your data sheet Break the compound up into its ions: The negative ions (anions) are across the top Find your negative ion and then look down into the chart to find the positive ion all : all compounds with those ions most : most compounds with those ions only with : only compounds containing whats listed Which elements are group 1? Group 2?

Slide 6

Solubility Table Find the solubility/state of the following compounds using the solubility table: (NH 4 ) 2 S AgCl PbSO 4 Sr(OH) 2 Fe(OH) 3 Au(NO 3 ) 3 AgCH 3 COO potassium carbonate iron (III) nitrate ammonium sulfite lead (IV) bromide

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Demo Results Which compounds produced solids? Could we have predicted which ones would form solids? Can you identify which compound made the precipitate? How? What ions do I have? How will they recombine?

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Properties of Water Water is polar Has a positive (hydrogen) and a negative (oxygen) end Bent shape and unequal sharing of electrons What does this mean can happen? Water molecules are attracted to one another Because polar, has several important properties: Boils at higher temp Why is this important? Hint: Think of how much of the earth is covered in water Bodies of water serve to regulate temperatures (absorb heat during the summer and release in winter)

Slide 9

Formation of Ice Is ice more or less dense than liquid water? How do you know? Water molecules spread out as it freezes making six-sided rings Look at a snowflake: how many points does it have? Space in between water molecules Makes ice less dense Why is this important? What might be affected if ice didnt float?