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3 years ago

Assuming complete dissociation, what is the ph of a 3.24 mg/l ba(oh)2 solution?

1 answer:

6 0

We need to first find the molarity of Ba(OH₂) solution.
A mass of 3.24 mg is dissolved in 1 L solution.
Ba(OH)₂ moles dissolved - 3.24 x 10⁻³ g/171.3 g/mol = 1.90 x 10⁻⁵ mol
dissociaton of Ba(OH)₂ is as follows;
Ba(OH)₂ --> Ba²⁺ + 2OH⁻
1 mol of Ba(OH)₂ dissociates to form 2OH⁻ ions.
Therefore [OH⁻] = (1.90 x 10⁻⁵)x2 = 3.8 x 10⁻⁵ M
pOH = -log[OH⁻]
pOH = -log (3.8 x 10⁻⁵)
pOH = 4.42
pH + pOH = 14
therefore pH = 14 - 4.42
pH = 9.58

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<h3>Explanation</h3>

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There's also an equilibrium between $\text{OH}^{-}$ and ${\text{H}_3\text{O}}^{+}$ ions.

${\text{OH}}^{-}\;(aq) + {\text{H}_3\text{O}}^{+} \;(aq) \to 2\; \text{H}_2\text{O} \;(l)$ .

$\text{OH}^{-}$ ions from $\text{NH}_4\text{OH}$ will shift the equilibrium between $\text{OH}^{-}$ and ${\text{H}_3\text{O}}^{+}$ to the right and reduce the amount of ${\text{H}_3\text{O}}^{+}$ in the solution.

The indicator equilibrium will shift to the right to produce more ${\text{H}_3\text{O}}^{+}$ ions along with the colored indicator ions. The solution will show a pink color.

What's the color of the solution after adding NH₄Cl?

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The equilibrium between $\text{OH}^{-}$ and ${\text{H}_3\text{O}}^{+}$ ions will shift to the left to produce more of both ions.

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3 years ago

Is this molecule polar or nonpolar?

lutik1710 [3]

The answer is nonpolar

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2 years ago

the radius of magnesium atom is 0.160nm. the radius of a magnesium ion is 7.2x 10^-11m. explain the difference in size between t

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Answer:

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Explanation:

magnesium reacts by losing two ions which makes it smaller in size.

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3 years ago

In the second step of this reaction, isocyanic acid reacts to form melamine and carbon dioxide: HNCO(l)→C3N3(NH2)3(l)+CO2(g) Bal

kykrilka [37]

Answer:

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3 years ago

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Answer:

e) pH is independent of concentration.

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I hope it helps!

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