Chemical Compounds

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Chemical Compounds
Chapter 15
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CRCT Preparation
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CRCT Preparation
Chapter 15
1. What kind of carbon backbone does the figure
represent? A an alkyne chain B a ring chain C a
branched chain D a straight chain
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CRCT Preparation
Chapter 15
1. What kind of carbon backbone does the figure
represent? A an alkyne chain B a ring chain C a
branched chain D a straight chain
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Chapter 15
2. Antacids usually contain bases. Which of the
following best describes the reaction between
antacids and stomach acid? A A neutralization
reaction occurs, producing neutral compounds. B
The products formed are more acidic than stomach
acid. C The antacid becomes bright red in the
presence of stomach acid. D The products formed
contain different elements than those contained
in antacid and stomach acid.
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Chapter 15
2. Antacids usually contain bases. Which of the
following best describes the reaction between
antacids and stomach acid? A A neutralization
reaction occurs, producing neutral compounds. B
The products formed are more acidic than stomach
acid. C The antacid becomes bright red in the
presence of stomach acid. D The products formed
contain different elements than those contained
in antacid and stomach acid.
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Chapter 15
3. Which of the following substances is a
lipid? A glucose B carbohydrate C fat D protein
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3. Which of the following substances is a
lipid? A glucose B carbohydrate C fat D protein
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4. A compound dissolved in water turns red
litmus paper blue and changes the indicator
bromthymol blue to dark blue. What kind of
compound is it? A an acid B a base C lemon
juice D table salt
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Chapter 15
4. A compound dissolved in water turns red
litmus paper blue and changes the indicator
bromthymol blue to dark blue. What kind of
compound is it? A an acid B a base C lemon
juice D table salt
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Chapter 15
5. A salt solution conducts an electric current,
but a sugar solution does not. Which of the
following statements best describes why a sugar
solution does not conduct an electric current? A
Sugar molecules are held together by ionic
bonds. B Covalent compounds cannot conduct
electric currents. C Sugar molecules form ions in
water. D Sugar molecules are not charged.
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Chapter 15
5. A salt solution conducts an electric current,
but a sugar solution does not. Which of the
following statements best describes why a sugar
solution does not conduct an electric current? A
Sugar molecules are held together by ionic
bonds. B Covalent compounds cannot conduct
electric currents. C Sugar molecules form ions in
water. D Sugar molecules are not charged.
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6. The pH of some common household substances is
listed in the table. Which substance would most
likely feel slippery? A lemon juice B vinegar C
milk D ammonia
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Chapter 15
6. The pH of some common household substances is
listed in the table. Which substance would most
likely feel slippery? A lemon juice B vinegar C
milk D ammonia
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Chapter 15
7. What factor does the pH scale measure? A the
concentration of sodium ions in a solution B the
concentration of hydroxide ions in a solution C
the concentration of glycogen ions in a
solution D the concentration of hydronium ions in
a solution
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7. What factor does the pH scale measure? A the
concentration of sodium ions in a solution B the
concentration of hydroxide ions in a solution C
the concentration of glycogen ions in a
solution D the concentration of hydronium ions in
a solution
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8. All organic compounds are based on which
element? A hydrogen B carbon C oxygen D nitrogen
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8. All organic compounds are based on which
element? A hydrogen B carbon C oxygen D nitrogen
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9. A chemist is identifying an unknown white
solid. The sample consists of a single compound.
The first step in the identification process
involves deciding if the compound is covalent or
ionic. Describe two pieces of information the
chemist could gather in order to decide if this
compound is covalent or ionic. Explain your
answer.
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• 9. Answer - Full-credit answers should include
  two of the following points
• The chemist could measure the compounds melting
  point. Melting points of ionic compounds are
  usually higher than those of covalent compounds.
• The chemist could see if the substance dissolves
  in water. Many ionic compounds dissolve in water,
  while most (but not all) covalent compounds do
  not.
• The chemist could measure the electrical
  conductivity of a solution containing the
  compound. Solutions of ionic compounds conduct
  electric current, while solutions of covalent
  compounds do not.

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10. When you add a small amount of a weak acid
to a sample of seawater, a neutralization
reaction occurs. What can you conclude about the
pH of seawater?
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10. Answer - The seawater must be basic if a
neutralization reaction happens when an acid is
added. So, the pH of the seawater must be greater
than 7.