Acids and Bases and Equilibrium

A buffer solution is made by dissolving ${\mathrm{HC}}_2{\mathrm{H}}_3{\mathrm{O}}_2 \mathrm{and} {\mathrm{NaC}}_2{\mathrm{H}}_3{\mathrm{O}}_2$ in water.

a. Write an equation that shows how this buffer neutralizes added acid.

b. Write an equation that shows how this buffer neutralizes added base.

For each of the following: (10.2,10.3)

1. $H_{2}S$   2.$H_{3}P{O}_4$

a. Write the formula for the conjugate base.

b. Which is the weaker acid?

For each of the following: 

1. HCN

2. $N{H_4}^{+}$

a. Write the formula for the conjugate base.

b. Which is the stronger acid?

Identify the conjugate acid-base pairs in each of the following equations: 

a. ${\mathrm{NH}}_3\left(aq\right)+{\mathrm{HNO}}_3\left(aq\right)⟶{\mathrm{NH}}_4^{+}\left(aq\right)+{{\mathrm{NO}}_3}^{-}\left(aq\right)$

b. ${\mathrm{H}}_2\mathrm{O}\left(l\right)+\mathrm{HBr}\left(aq\right)⟶{\mathrm{H}}_3{\mathrm{O}}^{+}\left(aq\right)+{\mathrm{Br}}^{-}\left(aq\right)$

Identify the conjugate acid-base pairs in each of the following equations:

a. ${\mathrm{HNO}}_2\left(aq\right)+{\mathrm{HS}}^{-}\left(aq\right)\rightleftarrows {\mathrm{NO}}_2^{-}\left(aq\right)+{\mathrm{H}}_2\mathrm{S}\left(g\right)$

b. $\mathrm{HCl}\left(aq\right)+{\mathrm{OH}}^{-}\left(aq\right)⟶{\mathrm{Cl}}^{-}\left(aq\right)+{\mathrm{H}}_2\mathrm{O}\left(l\right)$

Complete and balance each of the following

a. ${\mathrm{ZnCO}}_3\left(s\right)+{\mathrm{H}}_2{\mathrm{SO}}_4\left(aq\right)⟶$

b. $\mathrm{Al}\left(s\right)+\mathrm{HBr}\left(aq\right)⟶$

Complete and balance each of the following:

a. ${\mathrm{H}}_3{\mathrm{PO}}_4\left(aq\right)+\mathrm{Ca}\left(\mathrm{OH}{)}_2\right(s)⟶$

b. ${\mathrm{KHCO}}_3\left(s\right)+{\mathrm{HNO}}_3\left(aq\right)⟶$

Determine each of the following for a 0.050 M KOH solution: 

a. $\left[{\mathrm{H}}_3{\mathrm{O}}^{+}\right]$

b. pH

c. the balanced chemical equation for the reaction with ${\mathrm{H}}_2{\mathrm{SO}}_4$

d. millilitres of the KOH solution required to neutralize 40.0 ml of a $0.035 M H_2{\mathrm{SO}}_4$ solution

Determine each of the following for a 0.100 M HBr solution: 

a. $\left[{\mathrm{H}}_3{\mathrm{O}}^{+}\right]$

b. pH

c. the balanced chemical equation for the reaction with LiOH

d. millilitres of the HBr solution required to neutralize 36.0 mL of a 0.250 mL of LiOH solution

A 0.204 M NaOH solution is used to titrate 50.0 mL of an ${\mathrm{H}}_3{\mathrm{PO}}_4$ solution.

a. Write the balanced chemical equation.

b. What is the molarity of the ${\mathrm{H}}_3{\mathrm{PO}}_4$ solution if 16.4mL of the NaOH solution is required?

A 0.312 M KOH solution is used to titrate 15 mL of an ${\mathrm{H}}_2{\mathrm{SO}}_4$ solution.

a. Write the balanced chemical equation.

b. What is the molarity of the ${\mathrm{H}}_2{\mathrm{SO}}_4$solution if 28.2 mL of KOH solution is required?

Solution$A$ has a pH of$4.0$, and solution B has a $\mathrm{pH}$ of$6.0$. (10.6)

a. Which solution is mone acidic?

b. What is the $\left[{\mathrm{H}}_3{\mathrm{O}}^{+}\right]$in each?

c. What is the $\left[{\mathrm{OH}}^{-}\right]$in each?

A  0,205  M  NaOH solution is used to titrate $20.0 \mathrm{mL}$of a solution of ${\mathrm{H}}_2{\mathrm{SO}}_4$. If $45.6\mathrm{ml}$, of the $\mathrm{NaOH}$ solution is required to reach the endpoint, what is the molarity of the ${\mathrm{H}}_2{\mathrm{SO}}_4$ solution? $(0,7)$

$\left.{\mathrm{H}}_2{\mathrm{SO}}_4\left(aq\right)+2\mathrm{NaOH}\left(\alpha q\right)⟶2{\mathrm{H}}_2\mathrm{OND}\right)+{\mathrm{Na}}_2{\mathrm{SO}}_4\left(\alpha q\right)$

A 10.0-mL sample of vinegar, which is an aqueous solution of acetic acid,${\mathrm{HC}}_2{\mathrm{H}}_3{\mathrm{O}}_2$, requires $16.5 \mathrm{mL}$of a $0.500\mathrm{MNaOH}$ solution to reach the endpoint in a titration. What is the molarity of the acetic acid solution? $(10.7)$

Identify each of the following as an acid, base, or salt. and give its name: (10.1)

a.$LiOH$

b. $\mathrm{Ca}{\left({\mathrm{NO}}_4\right)}_2$

c. $\mathrm{HBr}$

d.$\mathrm{Ba}(\mathrm{OH}{)}_2$

e. ${\mathrm{H}}_{-}{\mathrm{CO}}_3$

Calculate the volume, in milliliters, of a $0,150 \mathrm{MNaOH}$ solution that will complesely neutralize each of the following: (10.7)

a. $25.0 \mathrm{mL}$of a ().286 M HC7 solution

b. $10.0 \mathrm{mL}$of a $0.560 {\mathrm{MHSO}}_4$solution

c.  $5.00 \mathrm{mL}$ of a $0.618 \mathrm{M}$ HBr solution

Identify each of the following as an acid, base, or salt, and give its name: (10.1)

a. ${\mathrm{H}}_3{\mathrm{PO}}_4$

b.$MgBr$?

c. ${\mathrm{NH}}_3$

d. ${\mathrm{HClO}}_2$

e.$\mathrm{NaCl}$

A buffer solution is made by dissolving ${\mathrm{H}}_3{\mathrm{PO}}_4\text{ and }{\mathrm{NaH}}_2{\mathrm{PO}}_4$ in  water(10.8)

A. Write an equation that shows how this buffer neutralizes added acid.

B. Write an equation that shows how this buffer neutralizes added base.

One of the most acidic lakes in the United States is Little Echo Pond in the Adirondacks in New York. Recently, this lake had a pH of 4.2, well below the recommended pH of 6.5.

a. What are the $\left[{\mathrm{H}}_3{\mathrm{O}}^{+}\right] \text{and }\left[{\mathrm{OH}}^{-}\right]$of Little Echo Pond?

b. What is the $\left[{\mathrm{H}}_3{\mathrm{O}}^{+}\right] \text{and }\left[{\mathrm{OH}}^{-}\right]$of a lake that has a pH of 6.5?

c. One way to raise the pH (and restore aquatic life) is to add limestone $CaC{O}_3$. How many grams of $CaC{O}_3$ are needed to neutralize $1.0 kL$ of the acidic water from Little Echo Pond if the acid is sulfuric acid?

${\mathrm{H}}_2{\mathrm{SO}}_4 \left(aq\right)+{\mathrm{CaCO}}_3 \left(s\right)⟶{\mathrm{CO}}_2 \left(g\right)+{\mathrm{H}}_2\mathrm{O} \left(l\right)+{\mathrm{CaSO}}_4 \left(aq\right)$

The daily output of stomach acid (gastric juice) is 1000 ml to 2000ml. Prior to a meal, stomach acid (HCl) typically has a pH of 1.42.

a. What is the $\left[{\mathrm{H}}_3{\mathrm{O}}^{+}\right]$of stomach acid?

b. One chewable tablet of the antacid Maalox contains 600mg of$CaC{O}_3$ Write the neutralization equation and calculate the milliliters of stomach acid neutralized by 2 tablets of Maalox.

c. The antacid milk of magnesia contains 400 mg per teaspoon. Write the neutralization equation, and calculate the number of milliliters of stomach acid neutralized by 1 tablespoon of milk of magnesia ( 1 tablespoon =3 teaspoons).