Acid: An acid dissociates and releases H+ ions in aqueous solution. A Bronsted- Lowry acid is a proton donor. A strong acid completely dissociates AND a weak acid partially dissociates. Can measure current through an acid to determine if strong and weak acid....
Acids
pH Scale and Strong Acids
pH Scale: Uses negative logarithm of powers of 10. More manageable scale. H Ion Concentration: Low value of [H+ (aq)] = high value of pH. A change in one pH number is 10x the [H+ (aq)]. Measuring pH: The electrode in pH meter measures electrical potential of H+...
Acid Dissociation Constant Ka
Acid Dissociation Constant Ka: Tells us extent of dissociation. No Ka value for strong acid as completely dissociate. Units are moldm-3. Ka = [ H +(aq)][ A−(aq)] [ HA(aq)] Use this one if Q asks for Ka expression. Equilibrium Constant: Ka changes with temperature so...
pH of Weak Acids
Ka can be calculated from equilibrium amounts. Approximations: Equation above can be simplified to equation below by assuming two things… Dissociation of Water: There is a small concentration of H+ from dissociation of water which is neglected. Therefore when HA...
pH of Bases
Determine if acid or alkali. Check if weak or strong before doing method. Also always check if 2OH or 2H as would be dibasic and would need to multiply conc x 2. Check in questions if given pKa or Ka. Kw: Ionic product of water- the ions in water H+ and OH-...