Chem- Chapter 11 Homework

How many moles of Ba(OH)2 are present in 205 mL of 0.800 M Ba(OH)2? Express your answer with the appropriate units.

0.164 mol

How many moles of HNO3 are present if 0.164 mol of Ba(OH)2 was needed to neutralize the acid solution? Express your answer with the appropriate units.

0.328 mol

What is the concentration of HNO3 if 0.328 mol are present in 895 mL of the solution? Express your answer with the appropriate units.

0.366 M

HCl(aq) and Fe(OH)3(s) Express your answer as a chemical equation. Identify all of the phases in your answer.

3HCl(aq)+Fe(OH)3(s)→3H2O(l)+FeCl3(aq)

Indicate whether each of the following statements is characteristic of an acid, a base, or both:

Acid turns litmus red Base produces OH− in water neutralizes acids has a slippery feel Both conducts an electrical current in solution

Write the formula of the conjugate base for acid HClO3. Express your answer as an ion.

ClO₃⁻

Write the formula of the conjugate base for acid HClO4. Express your answer as an ion.

ClO₄⁻

What is the chemical formula for the base iron(III) hydroxide? Express your answer as a chemical formula.

Fe(OH)3

Write the formula of the conjugate base for acid HF. Express your answer as an ion.

F⁻

H2SO3(aq) and Mg(OH)2(s) Express your answer as a chemical equation. Identify all of the phases in your answer.

H2SO3(aq)+Mg(OH)2(s)→MgSO3(aq)+2H2O(l)

H2SO4(aq) and KOH(aq) Express your answer as a chemical equation. Identify all of the phases in your answer.

H2SO4(aq)+2KOH(aq)→K2SO4(aq)+2H2O(l)

The formula for the selenate ion is SeO42−. Predict the formula for selenic acid. Express your answer as a chemical formula.

H2SeO4

Phosphoric acid dissociates to form dihydrogen phosphate and hydronium ion. Phosphoric acid has Ka of 7.5×10−3. Write the equation dissociation for phosphoric acid. Express your answer as a chemical equation. Identify all of the phases in your answer.

H3PO4(aq)+H2O(l)⇌H2PO4−(aq)+H3O+(aq)

Write the formula of the conjugate base for acid H2CO3. Express your answer as an ion.

HCO₃−

Why would the pH of your blood plasma increase if you breathe fast?

If you breathe fast, CO2 is expelled and the equilibrium shifts to lower[H3O+], which raises the pH.

What is the expression constant dissociation for phosphoric acid? Ka=[H3O+][H2PO−4]/[H3PO4] Ka=[H3O+]2[H2PO−4]/[H3PO4]2 Ka=[H3PO4]/[H3O+][H2PO−4] Ka=[H2PO−4]/[H3PO4]

Ka=[H3O+][H2PO−4]/[H3PO4]

Write the formula of the conjugate base for acid H2O. Express your answer as an ion.

OH−

Predict whether each of the following reactions contains mostly reactants or products at equilibrium:

Solution contains mostly reactants at equilibrium H3PO4(aq)+H2O(l)⇌H2PO4−(aq)+H3O+(aq) CN−(aq)+H2O(l)⇌HCN(aq)+OH−(aq) Solution contains mostly products at equilibrium NH3(aq)+HSO4−(aq)⇌NH4+(aq)+SO42−(aq) The solution will mostly contain the weaker acid and base species because the equilibrium favors the conversion of the stronger species into the weaker species. For example, among the weak acids and bases in Table 11.3, hydrogen sulfate (HSO4−) is the strongest weak acid, and hydroxide (OH−) is the strongest weak base. A reaction between those chemical species would produce a solution that mostly contains SO42− and H2O, where H2O is a weaker base than OH−.

Rank the following from most to least acidic.

[H3O+] = 10−2 Most pH = 2.5 pH = 4 [H3O+] = 10−5 pH = 9 Least

Carbonated cola is more acidic than coffee or even orange juice because cola contains phosphoric acid. What is the molar concentration of H3O+ in a cola that has a pH of 2.670? Express your answer with the appropriate units.

[H3O+] = 2.14×10−3 M

Calculate the [OH−] of each aqueous solution with the following [H3O+]: stomach acid, 2.0×10^−2M Express your answer using two significant figures. urine, 4.5×10^−6M Express your answer using two significant figures. orange juice, 2.8×10^−4M Express your answer using two significant figures. bile, 7.5×10^−9M Express your answer using two significant figures.

[OH−] = 5.0×10^−13 M [OH−] = 2.2×10^−9 M [OH−] = 3.6×10^−11 M [OH−] = 1.3×10−6 M

What is the pH of an aqueous solution with [H3O+] = 6×10−12 M ? Express the pH numerically using one decimal place.

pH = 11.2