# ka calculator from ph and molarity

This is a favorite problem for teachers to test! Ka = (10-2.4) 2 /(0.9 - 10-2.4) = 1.8 x 10-5. Calculate the pH value from the Ka by using the Ka to find the concentrations, or molarity, of the products and reactants when an acid or base is in an aqueous solution. Return to a listing of many types of acid base problems and their solutions. For "strong" acids and bases it is rather easy. More on this below. It is now possible to find a numerical value for Ka. This is only possible with acids and bases. Strong acid/base. The salt of a weak base behaves in solution as a weak acid, and its pH is calculated as for any other weak acid, eg if the acid is monobasic then [H+] = square root of (Ka x c), in this case if pKa = 10.4, Ka = 3.98 x 10^-11, [H+] = square root of(3.98 x 10^-11 x 0.13) = 2.27 x 10^-6M, pH = 5.64 Return to a listing of many types of acid base problems and their solutions . Create an ICE table. It can convert pH to H +, as well as calculate pH from the ionization constant and concentration. Note that x is Related to pH and Calculate Ka; As noted above, [H3O+] = 10-pH. The calculation of pH using molar concentration is different in case of strong acid/base and weak acid/base. Calculate the pH by taking the -log of the concentration of the H3O. Example #1: A student prepared a solution of salicylic acid (a monoprotic weak acid, MW = 138.123 g mol¯ 1) and measured the pH of the solution to be 2.430. References. Calculate the K a of a weak acid given the pH and other concentration data (not molarity) Return to Acid Base Menu. Here's the problem to be discussed: Problem #1: Codeine (C 18 H 21 NO 3) is a weak organic base. Hence the concentration of hydrogen ions in such solutions can be taken to be equal to the concentration of the acid. Calculate the K b given the pH and molarity. You start by using the pH of the solution to determine the concentration of the hydronium ions, H_3O^(+). Calculate K a from pH and Molarity. Return to the Acid Base menu. For "weak" acids and bases this is a little complicated, I will of course explain it if you request that (comment me for that). Since x = [H3O +] and you know the pH of the solution, you can write x = 10-2.4. Strong acids and bases are compounds that, for practical purposes, completely dissociate into their ions in water. With this pH calculator, you can determine the pH of a solution in a few ways.