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Find the pH of the following solutions and tell if they are acidic, basic or neutral. [OH-] = 1.0 x 10-2M[OH-] = 1.0 x 10-11M[OH-] = 3.5 x 10-2M[OH-] = 4.4 x 10-11

User Running Buffalo
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In this question, we have to find the pH of 4 solutions with the given OH- concentration, and in order to do that, we have to find the pOH first, and then we can find the pH, the formula for pOH is the same as pH:

pOH = -log [OH-]

Solution 1:

pOH = -log [1.0*10^-2]

pOH = 2

pH + pOH = 14

pH = 14 - 2

pH = 12, this is a BASIC solution

Solution 2:

pOH = -log [1.0*10^-11]

pOH = 11

pH + pOH = 14

pH = 14 - 11

pH = 3, this is an ACIDIC solution

Solution 3:

pOH = -log [3.5*10^-2]

pOH = 1.45

pH + pOH = 14

pH = 14 - 1.45

pH = 12.55, this is a BASIC solution

Solution 4:

pOH = -log [4.4*10^-11]

pOH = 10.36

pH + pOH = 14

pH = 14 - 10.36

pH = 3.64, this is an ACIDIC solution

User Aydan
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