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 ▸In the presence of ultraviolet radiation, cyclohexane reacts with bromine. A mixture of cyclic products are formed, including C6H11Br. Discuss each step of this reaction providing equations to show the mechanism.
What is the effect of temperature on K(equilibrium constant)?
A compound, HOCH2CH2CH2CH2COCl, reacts with itself to give a new compound. Give the IUPAC name for the starting compound, draw the mechanism for the formation of the new compound and give the prominant feature of the IR spectrum of the new compound.
What is meant by an ion being 'polarising' - and how does that determine if something is ionic/covalent?