What is the solubility in moles/liter for iron(III) hydroxide at 25 oC given a Ksp value of 2.0 x 10-39. Write using scientific notation and use 1 or 2 decimal places (even though this is strictly incorrect!)

9.28 × 10⁻¹¹ mol/L

Explanation:

Let's consider the solution of iron(III) hydroxide.

Fe(OH)₃(s) ⇄ Fe³⁺(aq) + 3 OH⁻(aq)

We can relate the solubility (S) of the hydroxide with the solubility product (Ksp) using an ICE chart.

      Fe(OH)₃(s) ⇄ Fe³⁺(aq) + 3 OH⁻(aq)

I                              0                  0

C                            +S               +3S

E                              S                 3S

The solubility product is:

Ksp = [Fe³⁺] × [OH⁻]³ = S × (3S)³ = 27 S⁴

the earth would become to overheated and everything alive on it will eventually die from overheating. plants will eventually die as well, water will evaporate, and it will be nothing but a hot planet without anything living on it.

the answer is b because, investigating whether another species of moth also drinks tears might be interesting, but it would not directly explain why this species of moth does.

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the scientist could experiment with moth repellent or oter ways to keep the moths away, but that would not answer his original question.