Reading Check Answers, p. 225
1. The pH scale is a number scale for measuring how acidic or basic a solution is.
2. Above pH 7
3. 100 times more basic
4. Colourless
5. (a) Yellow
(b) Green
(c) Blue
Reading Check Answers, p. 227
1. An acid has an H on the left side of its formula. (For acids containing the element carbon, the H may be on the right,
as in CH3COOH.)
2. (a) Hydrochloric (some students may say gastric)
(b) Acetic
(c) Sulfuric
3. Hydrofluoric acid
4. Perchloric acid
5. Corrosive means can burn tissues on contact.
Reading Check Answers, p. 228
1. A base has an OH on the right side of its formula.
2. (a) Mg(OH)2
(b) NaOH
3. NaOH
4. Caustic
(c) NH4OH
Cyu 5.1
Check Your Understanding Answers p. 233
1. (a) Sample answers: vinegar, lemon juice, carbonated drinks
(b) Sample answers: window cleaner, oven cleaner, detergent
2. (a) An acid forms a solution with a pH less than 7.
(b) A base forms a solution with a pH greater than 7.
(c) A neutral solution has a pH = 7.
3. It is unsafe to taste substances in the lab, even if they are food items, due to the possibility of contamination with a
poison.
4. (a) Solution A is more acidic.
(b) A is 1000 times more acidic than solution B.
5.
6. (a) Colourless
(b) Green
7. (a) Sour
(b) Forms bubbles
8. (a) Bitter
(b) No reaction
9. (a) Acetic acid
(b) CH3COOH
10. (a) Sulfuric acid
(b) H2SO4
11. (a) Magnesium hydroxide (b) Mg(OH)2
12. (a) Sodium hydroxide
(b) NaOH
13. (a) Hydrogen chlorate is changed to perchloric acid.
(b) Hydrogen sulphate is changed to sulfuric acid.
(c) Hydrogen fluoride is changed to hydrofluoric acid.
14. (a) Hydrochloric acid
(b) Nitric acid
15. At pH 8.5, the solution is slightly basic, so:
(a) Bitter
(b) Slippery
(c) Blue
Reading Check Answers, p. 238
1. Salt and water
2. Acid run-off (answer on page 229)
3. Acid rain
4. Acidic
5. Basic
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(c) Yellow
(c) Conducts
(c) Conducts
(c) Acetic acid
(d) No reaction
(d) Sulfuric acid
Check Your Understanding Answers p. 243 cyu 5.2
1. A salt is the ionic compound formed from the neutralization of a base with an acid.
2. Neutralization is a chemical reaction in which an acid and a base are combined, which then neutralize each other.
3. Base
4. Acid
5. Cesium
6. Sodium, gold, copper, zinc
7. Calcium carbonate is a base (even though it has no OH in the formula), and it is used to neutralize acid rain in the
lake water.
8. (a) Hydrogen
(b) Carbon dioxide
9. (a) Acid
(b) Base
(d) None of these
(f) Acid
(c) Base
(e) Salt
(g) Salt
10. (a) HF + NaOH NaF + H2O
(b) H3PO4 + 3KOH K3PO4 + 3H2O
(c) H2SO4 + Ca(OH)2 CaSO4 + 2H2O
(d) CH3COOH + NaOH NaCH3COO + H2O
(e) 3H2CO3 + 2Al(OH)3 Al2(CO3)3 + 6H2O
11. Blue. Magnesium burns to form magnesium oxide, and metal oxides form bases in water, making the resulting
solution basic. Litmus is blue in basic solutions.
12. Yellow. Sulfur burns to form sulfur oxides, and non-metal oxides form acids in water, making the resulting solution
acidic. Bromothymol blue turns yellow in acidic solutions.
Reading Check Answers, p. 247
1. Carbon
2. Hydrogen
3. For example: CaCO3, Al4C3, CO2
4. For example: FeCl2, (NH4)2SO3, PBr3
5. Carbon and hydrogen
Cyu 5.3
Check Your Understanding Answers p. 251
1. Organic chemistry is the study of compounds of carbon.
2. (a) Carbon
(b) Hydrogen
3. Accept all logical answers. For example, carbon can form stable bonds with many different elements, it can form up
to four bonds, and it has 3-D shapes.
4. (a) Organic
(b) Inorganic (but does contain an organic ion, so could also be considered organic)
(c) Inorganic
(e) Inorganic
(g) Organic
(i) Inorganic
(d) Organic
(f) Inorganic
(h) Inorganic
(j) Organic
5. A hydrocarbon is a compound formed from the elements carbon and hydrogen.
6. (a) Methane
(b) Natural gas
(c) For example: heating
7. Carbon, hydrogen, oxygen
8. A solvent is a liquid that can dissolve other substances.
9. (a) Solvent
(b) Fuel and some beverages and dissinfectants
(c) Sterilizer
10. (a), (b) , and (c) In each case, the alcohol has one oxygen atom in addition to the same number of carbons and
hydrogens.
11.
(a) Organic
(c) Inorganic
(e) Inorganic
(b) Organic
(d) Organic
(f) Organic
CHAPTER 5 REVIEW ANSWERS p. 252
1. (a) 7
2.
(b) Greater than 7
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(c) Less than 7
3. (a) 7
(b) 6
(c) 4
(d) 6.5–7.4
(e) 7.3–7.5
4. A 10 times increase in acidity
5. Red and blue litmus both turn red in an acid and blue in a base. In a neutral solution, red litmus stays red and blue
litmus stays blue.
6. (a) The chemical formula of an acid has an H on the left side. (Organic acids have the H on the right, as in
CH3COOH.)
(b) The chemical formula of a base has an OH on the left side.
7.
(a) HNO3
(c) NH4OH
(e) HCl
(g) Ca(OH)2
(b) NaOH
(d) Mg(OH)2
(f) H2SO4
(h) CH3COOH
8.
(a) Nitric acid
(d) Magnesium hydroxide
(g) Calcium hydroxide
(b) Sodium hydroxide
(e) Hydrochloric acid
(h) Acetic acid
(c) Ammonium hydroxide
(f) Sulfuric acid
9.
(a) Acids
(c) Bases
(e) Bases
(g) Acids
(b) Bases
(d) Both
(f) Acids
10. Neutralization is the reaction of an acid with a base to produce a salt and water.
11. (a) Basic
(b) Acidic
12. Lime is a base, so adding it to lake water allows it to neutralize the acid from acid precipitation.
13. (a) An organic compound is a compound of the element carbon, with the exception of a very few small carbon
compounds such as carbonate and some oxides.
(b) An inorganic compound is a compound that does not contain carbon, as well as a few small carbon compounds
such as carbon dioxide, carbon monoxide, and ionic carbonates.
14. (a) Carbon and hydrogen
(b) For example: natural gas heaters, manufacturing plastic, gasoline
15. (a) Carbon, hydrogen, and oxygen
(b) Fuels, solvents, cleaners
16. 100 times more basic
17. (a) Blue
(b) Yellow
(c) Pink
(d) Colourless
(e) Blue
18. (a) Hydrofluoric acid
(b) Perchloric acid
(c) Sulfuric acid
(d) Hydrochloric acid
19. (a) 3HNO3 + Al(OH)3 Al(NO3)3 + 3H2O
Reactants: nitric acid, aluminum hydroxide; products: aluminum nitrate, water
(b) HF + KOH KF + H2O
Reactants: hydrofluoric acid, potassium hydroxide; products: potassium fluoride, water
(c) 2H3PO3 + 3Ca(OH)2 Ca3(PO4)2 + 6H2O
Reactants: phosphoric acid, calcium hydroxide; products: calcium phosphate, water
(d) CH3COOH + NaOH3 NaCH3COO + H2O
Reactants: acetic acid, sodium hydroxide; products: sodium acetate, water
(e) H2SO4 + 2NaOH Na2SO4 + 2H2O
Reactants: sulfuric acid, sodium hydroxide; products: sodium sulphate, water
20. (a) 2HBr + Mg MgBr2 + H2
(b) 3H2SO4 + 2Al Al2(SO4)3 + 3H2
(d) 2HClO + Zn Zn(ClO)2 + H2
(c) 2HI + Ca CaI2 + H2
(e) 2H3PO3 + 6Na 2Na3PO3 + 3H2
21.
(a) Acid
(c) Base
(e) Salt
(b) Base
(d) Salt
(f) Acid
22.
(a) Organic
(c) Inorganic
(f) Organic
(b) Inorganic (does contain an
(d) Inorganic
(g) Inorganic
organic ion)
(e) Inorganic
(h) Inorganic
23.
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24. No. A solution cannot be both acidic and basic at the same time, even though it is
possible under some circumstances to contain both an acid and a base at the same
time. The solution will have only one pH value. If this value is greater than 7, the
solution is basic; at 7, it is neutral; and below 7, it is acidic.
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