The Chemistry of Acids and Bases

 The chemistry chemistry of acids and bases

Why is it important to know acids and bases? Body of water (safe for the sea creatures) Stomach •

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Cells of living organisms Industrial process

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Some properties of acids Produce H(as H!") in water  Taste  Taste sour# corrod corrode e metals $lectrolytes $lectrolytes (conduct electricity) %eact with bases to form a salt & water pH is less than ' turns blue litmus paper to red

Some properties of bases produce "H ions in water taste bitter# chaly*powdery chaly*powdery electrolytes# electrolytes# feel soapy*slippery react with acids to form salts and water pH greater than ' turns red litmus paper to blue

Acid/Base Denitions #1 Arrhenius (traditiona! +st scientist to study this Acids"  produce H  ions Bases" produce "H  ions

&on'uates" &on'uate base" base that remains when an acid donates a proton &on'uate acid" acid that formed when the base accepts a proton

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# Bronsted$%owry , proton is really -ust a hydrogen atom that has lost its electron Acids"  proton donor Bases" proton acceptor .Amphoteric/ can act as an acid*base •

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#) %ewis %ewis acid"  a substance that accepts an electron pair %ewis base" a substance that donates an electron pair

,CI0 1"2$1C3,TI4$ 53"6CH,%T ,CI0S start with H : elements

! elements

Hydro ; pre<8

1o hydro pre<8 ate ending become ;ic ending

ite ending become ;ous

&assication of Acids and Bases" Strenth Stron acids and bases"  ioni7e completely in water Weak acids and bases"  are only *ow to name bases"  cation  hydro8ide9 partially ioni7ed "H as ending &assication of Acids and Bases" +ranic or ,noranic ,noranic Acids" any substance that contains C" ! +ranic Acids" contains carbon • •

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&assication of Acids and Bases" Anhydrides (no water present in product! Base anhydrides"  ionic metals o8ides dissolve in water to form bases Acid anhydrides/ nonmetals o8ides dissolve in water to form acids • •

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Sat is formed when an acid anhydride reacts with a base anhydride

-eutrai.ation -eutrai.ation reaction double replacement reaction between acids and bases (w*c forms salt & water) diprotic acid# monoprotic acid# triprotic acid − −

Buers to lessen or absorb shoc bu=er solution resists changes in pH caused by the addition of limited amounts of a strong acid or a strong base signi!? − −

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p* concept acidity is measured by the (H !") basicity is measured by the ("H ) − −

0edo application of electroplating (a reaction wherein there is a base metal and cover it with silver) −

0edo 0eaction +idation" process by which a substance loses one or more electrons 0eduction / process by which substance gain electrons ."8idation is always accompanied by reduction hence reactions of this type are called %edo8 reactions P%"C$SS "8idation (o8idi7ed) %eduction (reduced) −

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$3$CT%"1S lost of e  gain of e 

,@$1T reducing agent o8idi7ing agent

the tendency to be o8idi7ed or reduced may be related to ioni7ation energy> The energy reAuired by an atom to lose an electron metals tend to lose electrons due to its low ioni7ation energy compared to nonmetals

+idation numbers system devised to help identify o8idi7ing and reducing agents no changes a system that help eep trac of electrons − − −

  loss electrons   gain electrons

+idation number determination the o8idation number of an atom in an uncombined element is  the o8idation number of any monoatomic ion eAuals its ionic charge in compounds# the o8idation number of many elements corresponds to the elementDs position in the periodic table + 9 $lements I @roup IB are always at :  $lements in @roup I, are always at !  ,luminum is always +  when combined with nonmetals  Hydrogen is :  "8ygen is  in most compounds and ions  The o8idation numbers of elements in compounds are written per atom − − −

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 The algebraic sum of the individual o8idation numbers of all atoms in the formula for a compound is   The algebraic sum of the individual o8idation numbers of all atoms in the formula for a polyatomic ion is eAual to its change