What volume (in mL) of 0.200 M NaOH do we need to titrate 40.00 mL of 0.140 M HBr to the equivalence point? NaOH + HBr – NaBr + H2O
Express your answer to three significant figures.

i'm pretty sure its b i might be wrong though!

it is the most commonly accepted one

the dissociation of nickel hydroxide is follows:

the concentration of hydroxide ion is

the equilibrium constant value of nickel hydroxide is = 6.1 * 10^-^1^6 and thus equilibrium equation can be written as:

thus, concentration of ni is 0.23 * 10^-^4 mol /l

answer; 4 electrons;