Besarnya pH larutan 0.74 gram Ca(OH)2 (Ar Ca=40,O=16,H=1) dalam 500 mL larutan adalah?
fatihahalhusna
![\displaystyle M=\frac{a}{Mr}\times\frac{1000}{V}=\frac{0,74}{74}\times\frac{1000}{500}=0,02\ M\\\\{[OH^-]}=2\times0,02=0,04\ M\\pOH=-\log[OH^-]=-\log0,04=2-\log4\\\\\boxed{\boxed{\bold{pH=12+\log4}}}](https://tex.z-dn.net/?f=%5Cdisplaystyle+M%3D%5Cfrac%7Ba%7D%7BMr%7D%5Ctimes%5Cfrac%7B1000%7D%7BV%7D%3D%5Cfrac%7B0%2C74%7D%7B74%7D%5Ctimes%5Cfrac%7B1000%7D%7B500%7D%3D0%2C02%5C+M%5C%5C%5C%5C%7B%5BOH%5E-%5D%7D%3D2%5Ctimes0%2C02%3D0%2C04%5C+M%5C%5CpOH%3D-%5Clog%5BOH%5E-%5D%3D-%5Clog0%2C04%3D2-%5Clog4%5C%5C%5C%5C%5Cboxed%7B%5Cboxed%7B%5Cbold%7BpH%3D12%2B%5Clog4%7D%7D%7D "\displaystyle M=\frac{a}{Mr}\times\frac{1000}{V}=\frac{0,74}{74}\times\frac{1000}{500}=0,02\ M\\\\{[OH^-]}=2\times0,02=0,04\ M\\pOH=-\log[OH^-]=-\log0,04=2-\log4\\\\\boxed{\boxed{\bold{pH=12+\log4}}}")
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