Acid Rap

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Chorus:

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

Chorus

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

Chorus

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

Chorus

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

Chorus

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

Acid Rap

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