4.7: Atoms, Molecules, and Ions (Exercises)
- Page ID
- 408991
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\(\newcommand{\avec}{\mathbf a}\) \(\newcommand{\bvec}{\mathbf b}\) \(\newcommand{\cvec}{\mathbf c}\) \(\newcommand{\dvec}{\mathbf d}\) \(\newcommand{\dtil}{\widetilde{\mathbf d}}\) \(\newcommand{\evec}{\mathbf e}\) \(\newcommand{\fvec}{\mathbf f}\) \(\newcommand{\nvec}{\mathbf n}\) \(\newcommand{\pvec}{\mathbf p}\) \(\newcommand{\qvec}{\mathbf q}\) \(\newcommand{\svec}{\mathbf s}\) \(\newcommand{\tvec}{\mathbf t}\) \(\newcommand{\uvec}{\mathbf u}\) \(\newcommand{\vvec}{\mathbf v}\) \(\newcommand{\wvec}{\mathbf w}\) \(\newcommand{\xvec}{\mathbf x}\) \(\newcommand{\yvec}{\mathbf y}\) \(\newcommand{\zvec}{\mathbf z}\) \(\newcommand{\rvec}{\mathbf r}\) \(\newcommand{\mvec}{\mathbf m}\) \(\newcommand{\zerovec}{\mathbf 0}\) \(\newcommand{\onevec}{\mathbf 1}\) \(\newcommand{\real}{\mathbb R}\) \(\newcommand{\twovec}[2]{\left[\begin{array}{r}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\ctwovec}[2]{\left[\begin{array}{c}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\threevec}[3]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\cthreevec}[3]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\fourvec}[4]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\cfourvec}[4]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\fivevec}[5]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\cfivevec}[5]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\mattwo}[4]{\left[\begin{array}{rr}#1 \amp #2 \\ #3 \amp #4 \\ \end{array}\right]}\) \(\newcommand{\laspan}[1]{\text{Span}\{#1\}}\) \(\newcommand{\bcal}{\cal B}\) \(\newcommand{\ccal}{\cal C}\) \(\newcommand{\scal}{\cal S}\) \(\newcommand{\wcal}{\cal W}\) \(\newcommand{\ecal}{\cal E}\) \(\newcommand{\coords}[2]{\left\{#1\right\}_{#2}}\) \(\newcommand{\gray}[1]{\color{gray}{#1}}\) \(\newcommand{\lgray}[1]{\color{lightgray}{#1}}\) \(\newcommand{\rank}{\operatorname{rank}}\) \(\newcommand{\row}{\text{Row}}\) \(\newcommand{\col}{\text{Col}}\) \(\renewcommand{\row}{\text{Row}}\) \(\newcommand{\nul}{\text{Nul}}\) \(\newcommand{\var}{\text{Var}}\) \(\newcommand{\corr}{\text{corr}}\) \(\newcommand{\len}[1]{\left|#1\right|}\) \(\newcommand{\bbar}{\overline{\bvec}}\) \(\newcommand{\bhat}{\widehat{\bvec}}\) \(\newcommand{\bperp}{\bvec^\perp}\) \(\newcommand{\xhat}{\widehat{\xvec}}\) \(\newcommand{\vhat}{\widehat{\vvec}}\) \(\newcommand{\uhat}{\widehat{\uvec}}\) \(\newcommand{\what}{\widehat{\wvec}}\) \(\newcommand{\Sighat}{\widehat{\Sigma}}\) \(\newcommand{\lt}{<}\) \(\newcommand{\gt}{>}\) \(\newcommand{\amp}{&}\) \(\definecolor{fillinmathshade}{gray}{0.9}\)The following questions are related to the material covered in this chapter. Answers to selected questions, only.
4.1-4.2 Matter and Changes
- Match the following terms with their meaning.
Terms Definitions (a) Mass a. a measure of the total quantity of matter in an object (b) Volume b. a measure of how strongly gravity pulls on an object (c) Weight c. a measure of the space occupied by an object - Identify each as either matter or not matter.
- a book
- hate
- light
- a car
- a fried egg
3. Give an example of matter in each phase: solid, liquid, or gas.
4. Does each statement represent a physical property or a chemical property?
- Sulfur is yellow.
- Steel wool burns when ignited by a flame.
- A gallon of milk weighs over eight pounds.
5. Does each statement represent a physical property or a chemical property?
- A pile of leaves slowly rots in the backyard.
- In the presence of oxygen, hydrogen can interact to make water.
- Gold can be stretched into very thin wires.
6. Does each statement represent a physical change or a chemical change?
- Water boils and becomes steam.
- Food is converted into usable form by the digestive system.
- The alcohol in many thermometers freezes at about −40 degrees Fahrenheit.
7. Does each statement represent a physical change or a chemical change?
- Graphite, a form of elemental carbon, can be turned into diamond, another form of carbon, at very high temperatures and pressures.
- The house across the street has been painted a new color.
- The elements sodium and chlorine come together to make a new substance called sodium chloride.
8. Distinguish between an element and a compound. About how many of each are known?
9. What is the difference between a homogeneous mixture and a heterogeneous mixture?
10. Identify each as a heterogeneous mixture or a homogeneous mixture.
- Salt is mixed with pepper.
- Sugar is dissolved in water.
- Pasta is cooked in boiling water.
11. Identify each as a heterogeneous mixture or a homogeneous mixture.
- air
- dirt
- a television set
Answers
-
- matter
- not matter
- not matter
- matter
- matter
8. An element is a fundamental chemical part of a substance; there are about 115 known elements. A compound is a combination of elements that acts as a different substance ; there are over 50 million known substances.
-
- homogeneous
- heterogeneous
- heterogeneous
Molecules and Molecular Compounds
- Which of these formulas represent molecules? State how many atoms are in each molecule.
- Fe
- PCl3
- P4
- Ar
- Which of these formulas represent molecules? State how many atoms are in each molecule.
- I2
- He
- H2O
- Al
- What is the difference between CO and Co?
- What is the difference between H2O and H2O2 (hydrogen peroxide)?
- Give the proper formula for each diatomic element.
- In 1986, when Halley’s comet last passed the earth, astronomers detected the presence of S2 in their telescopes. Why is sulfur not considered a diatomic element?
- What is the stem of fluorine used in molecule names? CF4 is one example.
- What is the stem of selenium used in molecule names? SiSe2 is an example.
- Give the proper name for each molecule.
- PF3
- TeCl2
- N2O3
- Give the proper name for each molecule.
- NO
- CS2
- As2O3
- Give the proper name for each molecule.
- XeF2
- O2F2
- SF6
- Give the proper name for each molecule.
- P4O10
- B2O3
- P2S3
- Give the proper name for each molecule.
- N2O
- N2O4
- N2O5
- Give the proper name for each molecule.
- SeO2
- Cl2O
- XeF6
- Give the proper formula for each name.
- dinitrogen pentoxide
- tetraboron tricarbide
- phosphorus pentachloride
- Give the proper formula for each name.
- nitrogen triiodide
- diarsenic trisulfide
- iodine trichloride
- Give the proper formula for each name.
- dioxygen dichloride
- dinitrogen trisulfide
- xenon tetrafluoride
- Give the proper formula for each name.
- chlorine dioxide
- selenium dibromide
- dinitrogen trioxide
- Give the proper formula for each name.
- iodine trifluoride
- xenon trioxide
- disulfur decafluoride
- Give the proper formula for each name.
- germanium dioxide
- carbon disulfide
- diselenium dibromide
Answers
-
- not a molecule
- a molecule; four atoms total
- a molecule; four atoms total
- CO is a compound of carbon and oxygen; Co is the element cobalt.
- H2, O2, N2, F2, Cl2, Br2, I2
- fluor-
-
- phosphorus trifluoride
- tellurium dichloride
- dinitrogen trioxide
-
- xenon difluoride
- dioxygen difluoride
- sulfur hexafluoride
-
- dinitrogen monoxide
- dinitrogen tetroxide
- dinitrogen pentoxide
-
- N2O5
- B4C3
- PCl5
-
- O2Cl2
- N2S3
- XeF4
-
- IF3
- XeO3
- S2F10
Ions and Ionic Compounds
- Explain how cations form.
- Explain how anions form.
- Give the charge each atom takes when it forms an ion. If more than one charge is possible, list both.
- K
- O
- Co
- Give the charge each atom takes when it forms an ion. If more than one charge is possible, list both.
- Ca
- I
- Fe
- Give the charge each atom takes when it forms an ion. If more than one charge is possible, list both.
- Ag
- Au
- Br
- Give the charge each atom takes when it forms an ion. If more than one charge is possible, list both.
- S
- Na
- H
- Name the ions from Exercise 3.
- Name the ions from Exercise 4.
- Name the ions from Exercise 5.
- Name the ions from Exercise 6.
- Give the formula and name for each ionic compound formed between the two listed ions.
- Mg2+ and Cl−
- Fe2+ and O2−
- Fe3+ and O2−
- Give the formula and name for each ionic compound formed between the two listed ions.
- K+ and S2−
- Ag+ and Br−
- Sr2+ and N3−
- Give the formula and name for each ionic compound formed between the two listed ions.
- Cu2+ and F−
- Ca2+ and O2−
- K+ and P3−
- Give the formula and name for each ionic compound formed between the two listed ions.
- Na+ and N3−
- Co2+ and I−
- Au3+ and S2−
- Give the formula and name for each ionic compound formed between the two listed ions.
- K+ and SO42−
- NH4+ and S2−
- NH4+ and PO43−
- Give the formula and name for each ionic compound formed between the two listed ions.
- Ca2+ and NO3−
- Ca2+ and NO2−
- Sc3+ and C2H3O2−
- Give the formula and name for each ionic compound formed between the two listed ions.
- Pb4+ and SO42−
- Na+ and I3−
- Li+ and Cr2O72−
- Give the formula and name for each ionic compound formed between the two listed ions.
- NH4+ and N3−
- Mg2+ and CO32−
- Al3+ and OH−
- Give the formula and name for each ionic compound formed between the two listed ions.
- Ag+ and SO32−
- Na+ and HCO3−
- Fe3+ and ClO3−
- Give the formula and name for each ionic compound formed between the two listed ions.
- Rb+ and O22−
- Au3+ and HSO4−
- Sr2+ and NO2−
- What is the difference between SO3 and SO32−?
- What is the difference between NO2 and NO2−?
Answers
- Cations form by losing electrons.
-
- 1+
- 2−
- 2+, 3+
-
- 1+
- 1+, 3+
- 1−
-
- the potassium ion
- the oxide ion
- the cobalt(II) and cobalt(III) ions, respectively
-
- the silver ion
- the gold(I) and gold(III) ions, respectively
- the bromide ion
-
- magnesium chloride, MgCl2
- iron(II) oxide, FeO
- iron(III) oxide, Fe2O3
-
- copper(II) fluoride, CuF2
- calcium oxide, CaO
- potassium phosphide, K3P
-
- potassium sulfate, K2SO4
- ammonium sulfide, (NH4)2S
- ammonium phosphate, (NH4)3PO4
-
- lead(IV) sulfate, Pb(SO4)2
- sodium triiodide, NaI3
- lithium dichromate, Li2Cr2O7
-
- silver sulfite, Ag2SO3
- sodium hydrogen carbonate, NaHCO3
- iron(III) chlorate, Fe(ClO3)3
- SO3 is sulfur trioxide, while SO32− is the sulfite ion.
Acids
- Give the formula for each acid.
- perchloric acid
- hydriodic acid
- Give the formula for each acid.
- hydrosulfuric acid
- phosphorous acid
- Name each acid.
- HF(aq)
- HNO3(aq)
- H2C2O4(aq)
- Name each acid.
- H2SO4(aq)
- H3PO4(aq)
- HCl(aq)
- Name an acid found in food.
- Name some properties that acids have in common.
Answers
-
- HClO4(aq)
- HI(aq)
-
- hydrofluoric acid
- nitric acid
- oxalic acid
- oxalic acid (answers will vary)