Ch. 2-3
Solutions-pH

Solutions
	Fluid mixtures - 2/+ substances mixed but not chemically bonded
	Solute-what gets dissolved
	Solvent-what it gets dissolved in
	Solutions are described in terms of solute
		15% salt solution means:
			15g of salt in 100mL of solution
	Water is the universal solvent
	Saturated-as much solute as possible
	Super-saturated-
		too much solute
		settles/precipitates to bottom(top)
	Aqueous solutions-solvent is water
Disassociation
		Molecule will separate when put in H2O
	Acids
		Any substance that when dissolved in water produces Hydrogen ions [H+]
		Hydronium ion- H3O-
			Produced when H+ bonds with H2O
		HCl + H2O --> H2O + Cl- + H+
	Base
		Any substance when dissolved in water produces hydroxide ions [(OH)-]
		KOH + H2O --> H2O + K+ + (OH)-
	Salt
		NaCl + H2O --> H2O + Na+ + Cl-
		Does not produce H+ or (OH)-
pH Scale
	Acidity
		Acids
		Corrode
		"not so bad"
		pH < 7
		i.e. stomach acid 1.0-1.5, vinegar 5.5
	Alkalinity
		Bases
		"dig-in"
		"always wear goggles!!!!"
		pH > 7
		i.e. saliva 8 (kills germs)
	pH of 5 has 10 x more H+ than a pH of 6
	pH of 9 has 10 x more OH- than a pH of 8
	Clorox + ammonia =>chlorine gas (poisonous)
Buffer
	Any substance that neutralizes an acid/base
		Acid neutralized by base
		Base neutralized by acid





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