1. Acids and Metals
Acids react with certain metals to produce hydrogen gas
and the metal salt.
metal acid metal salt hydrogen gas
Magnesium reacts rapidly
with acid and forms a salt
of magnesium and H2 gas.

2. Acids and Carbonates
Acids react with carbonates or bicarbonates (hydrogen
carbonate), to produce carbon dioxide gas, water, and an
ionic compound (salt).
The acid reacts with CO32− to produce carbonic acid,
H2CO3, which breaks down rapidly to CO2 and H2O.
metal acid carbon dioxide metal salt water

3. Acid Rain
Acid rain
is a term given to precipitation, such as rain, snow, hail, or fog, that has a pH of 5.6 or less.
is formed when sulfur impurities from coal and oil react with water and oxygen gas to form H2SO4.
degrades marble statues and limestone structures.
interferes with photosynthesis, killing plants and trees.

4. Acid Rain
A marble statue in Washington Square Park has been eroded by acid rain.
Acid rain has severely damaged forests in Eastern Europe.

5. Learning Check Write the products and the balanced chemical equation
for each of the following reactions of acids.

6. Solution Write the products and the balanced chemical equation
for each of the following reactions of acids.

7. Neutralization Reactions
Neutralization is the reaction of an acid, such as HCl
and a base, such as NaOH.
acid base salt water
The net ionic equation shows that H+ combines with OH− to form H2O, leaving the ions Na+ and Cl- in solution
Crossing out spectator ions we get

8. Guide to Balancing an Equation for Neutralization

9. Balancing Neutralization Reactions
Write the balanced equation for the neutralization of
magnesium hydroxide and nitric acid.
Step 1 Write the reactants and products.
Step 2 Balance the H in the acid with the OH in the
base.

10. Balancing Neutralization Reactions
Write the balanced equation for the neutralization of
magnesium hydroxide and nitric acid.
Step 3 Balance the H2O with the H and OH.
Step 4 Write the salt from the remaining ions.

11. Learning Check
Write the balanced equation for the reaction of the base KOH with the strong acid, H2SO4.

12. Solution Write the balanced equation for the reaction of the base
KOH with the strong acid, H2SO4.
Step 1 Write the reactants and products.
Step 2 Balance the H in the acid with the OH in the
base.

13. Solution Write the balanced equation for the reaction of the base
KOH with the strong acid, H2SO4.
Step 3 Balance the H2O with the H and OH.
Step 4 Write the salt from the remaining ions.

14. Learning Check
Select the correct group of coefficients for the following
neutralization equations. 1.
A. 1, 3, 3, B. 3, 1, 1, C. 3, 1, 1, 3 2.
A. 3, 2, 2, B. 3, 2, 1, C. 2, 3, 1, 6

15. Solution Select the correct group of coefficients for the following
neutralization equations. 1.
Answer is C. 3, 1, 1, 3. 2.
Answer is B. 3, 2, 1, 6.

16. Acid–Base Titration Titration
is a laboratory procedure often used to determine the molarity of an acid.
uses a base, such as NaOH, to neutralize a measured volume of an acid.
Base (NaOH)
Acid
solution

17. Indicator An indicator is added to the acid in the flask.
causes the solution to change color when the acid is neutralized.

18. End Point of Titration At the end point,
moles of OH− equal moles of H3O+ in the acid, and
the indicator has a faint, permanent pink color.

19. Concentration of the Acid
From the measured volume of the NaOH solution at
the end point and its molarity, we calculate
the number of moles of NaOH used,
the moles of acid in the flask, and
the concentration of the acid.

20. Guide to Calculations for an Acid–Base Titration

21. Calculating Molarity from a Titration with a Base
What is the molarity of an HCl solution if 18.5 mL of a
0.225 M NaOH are required to neutralize 10.0 mL HCl?
Analyze the Problem.

22. Calculating Molarity from a Titration with a Base
What is the molarity of an HCl solution if 18.5 mL of a
0.225 M NaOH are required to neutralize 10.0 mL HCl?
Step 1 Write the balanced equation for the
neutralization.
Step 2 Write a plan to calculate molarity or volume.
liters molarity moles mole–mole moles divide molarity
of NaOH NaOH NaOH factor HCl by liters

23. Calculating Molarity from a Titration with a Base
What is the molarity of an HCl solution if 18.5 mL of a
0.225 M NaOH are required to neutralize 10.0 mL HCl?
Step 3 State equalities and conversion factors.
1 L NaOH and mole NaOH
0.225 mole NaOH L NaOH
1 mole of NaOH = 1 mole of HCl
1 mole NaOH and 1 mole HCl
1 mole HCl mole NaOH

24. Calculating Molarity from a Titration with a Base
What is the molarity of an HCl solution if 18.5 mL of a
0.225 M NaOH are required to neutralize 10.0 mL HCl?
Step 4 Set up the problem to calculate the needed quantity.
L NaOH x mole NaOH x 1 mole HCl
1 L NaOH mole NaOH
= mole HCl = M HCl
L HCl

25. Learning Check Calculate the volume in liters of 2.00 M H2SO4 required
to neutralize 50.0 mL ( L) of 1.00 M KOH.
A L
B L
C L

26. Solution Calculate the volume in liters of 2.00 M H2SO4 required
to neutralize 50.0 mL ( L) of 1.00 M KOH.
H2SO4(aq) + 2KOH(aq) K2SO4(aq) + 2H2O(l)
Step 1 Write the balanced equation for the neutralization.
Step 2 Write a plan to calculate molarity or volume.
liters molarity moles mole–mole moles molarity liters
of KOH KOH KOH factor H2SO H2SO H2SO4

27. Solution Calculate the volume in liters of 2.00 M H2SO4 required
to neutralize 50.0 mL ( L) of 1.00 M KOH.
Step 3 State equalities and conversion factors.
1 L KOH and mole KOH
1.00 mole KOH L KOH
2 moles of KOH = 1 mole of H2SO4
2 moles KOH and 1 mole H2SO4
1 mole H2SO moles KOH

28. Solution Calculate the volume in liters of 2.00 M H2SO4 required
to neutralize 50.0 mL ( L) of 1.00 M KOH.
Step 3 State equalities and conversion factors.
1 L of H2SO4 = moles of H2SO4
1 L H2SO and moles H2SO4
2.00 moles H2SO L H2SO4

29. Solution Calculate the volume in liters of 2.00 M H2SO4 required
to neutralize 50.0 mL ( L) of 1.00 M KOH.
Step 4 Set up the problem to calculate the needed quantity.
L KOH x mole KOH x 1 mole H2SO4
1 L KOH moles KOH
x 1 L H2SO = L H2SO4
2.00 moles H2SO4
Answer is A.