Acids & Bases

Acids & Bases - Arrhenius - Acids produce hydrogen...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Arrhenius - Acids produce hydrogen ions - Bases produce hydroxide ions Bronsted-Lowry - Acids are proton donors - Bases are proton acceptors Lewis - Acids are electron-pair acceptors - Bases are electron-pair donors Understand notions of conjugate acid-base pairs. Recall: acidity increases from left to right as well as from top to bottom in the periodic table Whether an acid is strong or weak depends on how completely it ionizes in water. A strong acid is one that dissociates completely in water - HCl is an example. - Hydrofluoric acid is not a strong acid (i.e. much of the HF remains undissociated when put into a solution) The strength of the acid is directly related to how much the products are favored over the reactants. K a = [H 3 O + ][A - ]/[HA] - This expression is for the acid dissociation reaction ; not to be confused with the equilibrium dissociation reaction. - The same concepts apply as in equilibrium (Recall that if K eq > 1, then the equilibrium is favored towards the products and the reaction will be favored in the forward direction. Likewise if K a > 1, then the products are favored this tells us that it’s a relatively strong acid because much of the acid has dissociated into its constituent ions ) - If K a < 1, this is indicative of a relatively weak acid. Strong acids: HI, HBr, HCl, HClO 4 , H 2 SO 4 , HNO 3 The more stable an acid’s conjugate base, the stronger the acid . - Smaller conjugate bases are not able to spread out their negative charge, making them less stable than strong acids whose conjugate bases can spread out their negative charge. K b = [HB + ][OH - ]/[B] The same idea applies: stronger bases have high K b values Common strong bases : Group 1 hydroxides (i.e. NaOH), Group 1 oxides (i.e. Li 2 O), some group 2 hydroxides (barium hydroxide, strontium hydroxide, calcium hydroxide), and metal amides (i.e. NaNH 2 )
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 11/07/2010 for the course CBN 356 taught by Professor Merill during the Spring '08 term at Rutgers.

Page1 / 4

Acids &amp;amp; Bases - Arrhenius - Acids produce hydrogen...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online