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What concentration of the barium ion, ba2+, must be exceeded to precipitate baf2 from a solution that is 1.00×10−2 m in the fluoride ion, f−? ksp for barium fluoride is 2.45×10−5 . express your answer with the appropriate units?

User Tianwei
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2 Answers

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Answer: The concentration of barium ions that must exceed to precipitate the salt is 0.245 M

Step-by-step explanation:

Solubility product is defined as the product of concentration of ions present in a solution each raised to the power its stoichiometric ratio. It is represented as
K_(sp)

Barium fluoride is an ionic compound formed by the combination of 1 barium ion and 2 fluoride ions.

The equilibrium reaction for the ionization of barium fluoride follows the equation:


BaF_2(s)\rightleftharpoons Ba^(2+)(aq.)+2F^-(aq.)

The solubility product for the above reaction is:


K_(sp)=[Ba^(2+)]* [F^-]^2

We are given:


[F^-]=1.00* 10^(-2)M\\\\K_(sp)=2.45* 10^(-5)

Putting values in above equation, we get:


2.45* 10^(-5)=[Ba^(2+)]* (1.00* 10^(-2))^2


[Ba^(2+)]=(2.45* 10^(-5))/((1.00* 10^(-2))^2)=0.245M

Hence, the concentration of barium ions that must exceed to precipitate the salt is 0.245 M

User Imsrch
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Answer is: concentration of the barium ion is 0.245 M.

Chemical reaction: BaF₂ → Ba²⁺ + 2F⁻.

[F⁻] = 1.00·10⁻² M.

Ksp = 2.45·10⁻⁵.

Ksp = [Ba²⁺] · [F⁻]².

[Ba²⁺] = Ksp ÷ [F⁻]².

[Ba²⁺] = 2.45·10⁻⁵ ÷ (1.00·10⁻² M)².

[Ba²⁺] = 0.245 M.

User Skytree
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