pH by definition is given as -log10(cH+) or log10(1/cH+), where cH+ is the concentration of the H+ ions in the solution.Similarly, pOH= -log10(cOH-) pH + pOH= 14KOH is basic so we can calculate the pOH, which is pOH= -log10(cOH-)=-log10(0.002)= 2.69pH=14-2.69=11.31