Calculate the mass of strontium hydroxide required to make a 450-mL solution with a pOH of 4.00.

Step 1: Find pOH. I found that pOH is 10.

The next steps is where I'm stuck.

Step 2 :Calculate the hydroxide ion concentration. Express your answer in scientific notation.
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mol/L.
Answer:
Step 3: Calculate the concentration of strontium hydroxide. Express your answer in scientific notation.
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mol/L.
Answer:

Step 4: Determine the number of moles of Sr(OH)2(aq). Express your answer in scientific notation.
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mol.
Answer:

Step 5: Determine the mass of Sr(OH)2(s)

1 answer

The pOH is 10.
To convert pOH = 10 to OH^-, it is
pOH = -log(OH^-)
10 = -log(OH^-)
-10 = log(OH^-)
Take antilog of both sides.
1 x 10^-10 = OH^-