Calculate the PH of the 0.4g of NaoH in water to give 200ml of solution

Answer 1

Start with the definition:
pH=14-log(concentraiionOH)
but concentration of OH is moles/liters
OH concentration= (.4g/40g/mole)/.2liters

so do the math:
pH=14-log(.05)
which is about 12.5 work it out. Yep, pH is alkaline.