Chemistry Chapter 7: Acids & Bases

Question 1

Acid

Answer 1

Substance that releases H+ ions when dissolved in water.

Question 2

Base

Answer 2

Substance that releases OH- ions in aqueous solution.

Question 3

Types of Acids

Answer 3

1. Binary - only 2 elements, hydrogen and another
2. Oxyacid - has hydrogen, oxygen, and another element (hydrogen, & polyatomic ion)

Question 4

Naming Binaries

Answer 4

1. Use hydro as the prefix.
2. Add the stem name of the second element.
3. Add an ic ending

Question 5

Naming Oxys

Answer 5

1. The polyatomic ion ending, ate, is dropped.
2. The ending ic acid is added to the stem name

Note: No “hydro” prefix

Question 6

Common Properties of Both Acids and Bases

Answer 6

1. Soluble in water
2. Conductors
3. Can be corrosive

Question 7

Type of Oxide to Produce Acids/Bases When Dissolved in Water

Answer 7

Acids: non-metal oxides
Bases: metal oxides

Question 8

Taste, Feel and pH range of Acids and Bases

Answer 8

Acids: sour, no feel, range 0-6.9
Base: bitter, slippery, range 7.00001-14

Question 9

Colour of litmus paper when placed in solution

Answer 9

Acids: red
Bases: blue

Question 10

Colour of bromothymol blue
solution when added into the
solution.

Answer 10

Acids: Yellow
Bases: Blue-Purple

Question 11

Acids & Bases: Reactivity w/ metals

Answer 11

Acids: Reactive to produce hydrogen gas
Bases: null

Question 12

Acids & Bases: Reaction with carbonate
compounds

Answer 12

Acids: produce carbon dioxide
Bases: null

Question 13

Making an acid or base

Answer 13

There are two steps in forming an acid or a base from an element:
1. Combustion of the element to form an oxide (see Section 6.9)
2. Combining the oxide and water in a synthesis reaction
Ex. C + O2 -> CO2
CO2 + H20 -> H2CO3

Note: In summary, a non-metal oxide combined with water forms an acid. A metal oxide combined with water forms a base

Question 14

pH

Answer 14

• Stands for “Power of Hydrogen”
• a measure of how acidic or basic a
  solution is (concentration of hydrogen ions)

Question 15

pH scale

Answer 15

a numerical scale ranging from
0 to 14 that is used to compare the acidity
of solutions

Question 16

Logarithmic scale

Answer 16

one unit on the (pH) scale is equivalent to a
tenfold change in concentration.

Ex. pH of 3 is 10 times more
acidic than a pH of 4, and pH of 10 is 1000 times less basic than a pH of 13

Question 17

Neutralization reaction

Answer 17

• chemical reaction where an acid and a base react to form an ionic compound (a salt) and
  water. The resulting pH is closer to 7.
• All acid-base neutralization reactions are double displacement reactions
• resulting ionic compound may remain dissolved in water or may form a precipitate

Question 18

Neutralization Applications

Answer 18

-Chemical Spills:
* Ex. train was hauling sulfuric acid, derailed and spilled into the Blanche River. The emergency response crew added calcium oxide (reacts w/ H20 to make Ca(OH)2) to the river.
-Antacids
* Antacids provide relief by neutralizing stomach acid (HCl). Most common active ingredients in antacids are hydroxide and carbonate compounds.

Question 19

Acid Usage Examples

Answer 19

• Acid leaching (removing heavy metals from soils)
• In beauty products (“balancing pH”)
• digestion
• Foods (adding flavours, preservation)

Question 20

Base Usage Examples

Answer 20

• Cleaning products
• Antacids
• Neutralize acids (ex. chemical spills)
• Electrical conductors

Question 21

Environmental Applications of Neutralization (Acids & Bases)

Answer 21

• changing the acidity of soil that has been contaminated
• changing the acidity of water bodies (usu. add calcium hydroxide)

Question 22

Consumer Applications of Neutralization (Acids & Bases)

Answer 22

• Antacids
• Using shampoo and conditioners
• Regulating pool water through increasing the acidity or bascisity ph to make it as neutral as possible