Acid Rap

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substances found in so many places
can be called either acids or bases
acid is a proton donator
base is a proton acceptor
why would a compound want to give away its proton
actually makes sense, this ain’t no con
atoms come together, share their electrons
makes a compound, forms a covalent bond
electronegative, one of those atoms is most
wants to hold both electrons, brings ‘em real close
don’t know which one they’re near more
look at the periodic table to be sure
electronegativity increases as you go right
and up, chlorine pulls them electrons real tight
shares them with hydrogen, you got HCl
oh yeah a proton is a hydrogen ion, well
that’s why HCl is such a strong acid
chlorine takes hydrogen’s electron for itself  kid
in a polar solvent like water it depends
H+ floats around lookin’ for a friend
H+ means it’s a hydrogen ion brother
lost an electron, it really needs another
lookin’ to bind, ions are highly unstable
lookin’ everywhere, even under the table
acids and bases dissociate in water
only strong ones do completely,  maintain order
you can figure out how many protons there are
to calculate pH, you’re not very far
pH is a scale, acids on the low side
0 to 14, bases on the high
7 in the middle, the pH of water
weak acids and bases on the border
0.01 molar HCl
a strong acid really dissociates well
in water that means 0.01 H+ concentration
man this is easier than multiplication
pH= -log proton concentration
plug in –log (0.01)
almost done, I aint playin’ you
pH of this solution is 2
weaker acids don’t dissociate completely
need dissociation constant to figure it out neatly
dissociation constant equals Ka
Ka equals [H+] [A] over HA
that means you have a relation
hydrogen ions, conjugate base in an equation
and the undissociated acid molecules
that’s the HA, you’ll get it, just follow these rules.
figure out pH for acetic acid
concentration of that vinegar is 0.2 molar kid
Ka is 1.8 x 10-5
set up and plug in, that ain’t no jive
number of hydrogen ions is equal to  x
same as conjugate base you know what’s next
concentration of weak acid doesn’t change fool
Ka equals x2 over 0.2
solve for x and you get number of hydrogen ions
now you know how to get your pH on.
all you gotta do is take negative log
calculated pH is 2.7, dawg