Calculate the pH of a 0.0131 mol dm^-3 solution of calcium hydroxide at 10 degrees centigrade.

Multiply by 2 because calcium hydroxide = Ca(OH)2 so 2 x [OH-] per molecule.[OH-] = 0.0131 x 2 = 0.0262
Insert [OH-] value into the equilibrium equation along with the value of Kw at 10 degrees centigrade 2.93 x 10^-15 (from data tables). This gives the value for [H=].[H+] = (Kw/[OH-] ) = 2.93 x 10^-15 / 0.0262 = 1.118 x 10^-13
Finally, insert [H+] value into pH equation.pH = -log (1.118 x 10^-13) = 12.95

EW

Related Chemistry A Level answers

All answers ▸

0.04 moles of sulfur trioxide is placed in a flask (1.50dm^3) and allowed to reach equilibrium at 600 degrees. If 30% of the sulfur trioxide decomposes to sulfur dioxide and oxygen - what is the equilibrium constant?


Explain, in the context of catalysis, the term heterogeneous and describe the first stage in the mechanism of this type of catalysis.


Analysing IR spectrum.


In the presence of ultraviolet light, ethane and chlorine react to give a mixture of products. What are the products of this reaction?