Exam 4 Chapter 15

How many oxide ions (O-2) are needed to balance the positive charge of a titanium ion (Ti+4)? A) 2 B) 1 C) 3 D) 4 E) 6

A) 2

What is the main difference between a dipole-dipole interaction and a dipole-induced dipole interaction? A) Both are similar, but one involves a temporary dipole created by a permanent dipole. B) Dipole-dipole interactions are weaker because the dipoles are permanent. C) Dipole-induced dipole interactions are stronger because the induced dipoles can be formed at any time.

A) Both are similar, but one involves a temporary dipole created by a permanent dipole.

Which of the following bonds would be the most polar? A) C-F B) C-Cl C) C-Br D) C-I

A) C-F

Which of the following molecules is most likely to show the strongest hydrogen bonding? A) CH3OH B) CH3SH C) CH4 D) H-C≡C-H

A) CH3OH

Which of the following molecules contains a polar bond? A) H-F B) Cl-Cl C) H-H D) F-F

A) H-F

Which of the following molecules is most likely to show a dipole-dipole interaction? A) H2S B) CO2 C) CH4 D) H-C≡C-H

A) H2S

What is the compound that forms if you react potassium and sulfur? A) K2S B) KS C) SP D) PS2

A) K2S

Which of the following molecules contains an ionic bond? A) MgCl2 B) Cl2 C) SF3 D) PO-3

A) MgCl2

What it the main difference between a covalent bond and an ionic bond? A) One is the sharing of a pair of electrons, the other is the transfer of at least one electron. B) One involves electrons, the other does not involve any electrons. C) The electrons in both types of bonding undergo an exchange. D) The electrons are traded between the two atoms and this keeps the atoms close. E) Both bonds are the same, but named different to describe different atoms involved.

A) One is the sharing of a pair of electrons, the other is the transfer of at least one electron.

What property of alloys make them ideal for developing new materials? A) The characteristics of the material change depending on how much of each component is present. B) Alloys are very rigid and are extremely resistant to chemical decomposition. C) The size of the atoms involved is directly related the electrical conductivity.

A) The characteristics of the material change depending on how much of each component is present.

If an ionic bond is stronger than a dipole-dipole interaction, how can water dissolve an ionic compound? A) The ion-dipole interactions of a bunch of water molecules gang up on the strong ionic bond and pull it into the solution. B) The ionic bond is weakened by the ion-dipole interactions and ionic repulsion ejects the ions from the crystal. C) The ion-dipole interaction causes the ions to heat up and vibrate free of the crystal. D) The ions never overcome their interatomic attraction and therefore are not soluble.

A) The ion-dipole interactions of a bunch of water molecules gang up on the strong ionic bond and pull it into the solution.

Why is metal shiny? A) The loose electrons reflect most wavelengths of light. B) The electrons transmit most wavelengths of light. C) The electrons absorb each light wave. D) The electrons emit light due to electronic excitation.

A) The loose electrons reflect most wavelengths of light.

Which of the following describes how metal atoms behave in a bulk metallic object? A) The metal ion shares its outermost electrons freely with its neighbors. B) The metal atoms have limited interaction with neighboring atoms. C) The metal atom shares its electrons in a very directional manner. D) The metal atom shares its electrons with only one other atom.

A) The metal ion shares its outermost electrons freely with its neighbors.

What is happening at the molecular level when a polar molecule like water interacts with a typical sodium ion? A) The water molecule aligns such that the oxygen interacts with the sodium. B) The water molecule aligns such that the hydrogens interact with the sodium. C) The polarity of the water molecule is altered making the oxygen more positively charged. D) The polarity of the water molecule is altered making the hydrogens more negatively charged.

A) The water molecule aligns such that the oxygen interacts with the sodium

What is a molecule? A) a group of atoms that are held together by covalent bonds B) a group of atoms that are held together by ionic bonds C) pair of atoms sharing a set of valence electrons D) pair of shared valence electrons E) group of covalent compounds held together by ionic bonds

A) a group of atoms that are held together by covalent bonds

What is a hydrogen bond? A) a special type of dipole-dipole attraction involving hydrogen bound to a highly electronegative atom B) a special type of dipole-dipole attraction involving hydrogen bound to any other atom C) a special type of dipole-dipole attraction involving hydrogen bound to another hydrogen atom D) a special type of attraction involving any molecules that contain hydrogens

A) a special type of dipole-dipole attraction involving hydrogen bound to a highly electronegative atom

Which of the following statements best describes a relatively polar bond? A) a very electronegative atom and a weakly electronegative atom are covalently bound B) two very electronegative atoms are covalently bound C) two very electronegative atoms undergo ionic bonding D) two weakly electronegative atoms undergo ionic bonding

A) a very electronegative atom and a weakly electronegative atom are covalently bound

What is the name of this polyatomic ion? CH3CO2-1 A) acetate B) monocarboxylate C) carboxylic D) acidic E) acetic

A) acetate

What needs to be done to convert a neutral nitrogen atom into an N-3 species? A) add three electrons B) remove three electrons C) remove three protons D) add three protons

A) add three electrons

Which of the following would be a negative ion with a single charge? A) an atom with 11 protons and 12 electrons B) an atom with 11 protons and 11 electrons C) an atom with 12 protons and 11 electrons D) an atom with 10 protons and 12 electrons

A) an atom with 11 protons and 12 electrons

Which of the following is not a property of metal? A) does not conduct heat well B) conducts electricity C) is shiny D) is strong, but can be bent

A) does not conduct heat well

The neon atom tends NOT to lose any electrons because A) of its relatively strong effective nuclear charge. B) that would result in a negative ion. C) its electrons are paired together within the same orbitals. D) the ionization energy is so high

A) of its relatively strong effective nuclear charge

Chlorine, Cl2, is a gas at room temperature, but bromine, Br2, is a liquid. Explain. A) Chlorine atoms are larger and this makes the formation of induced dipole-induced dipole attractions more favorable. B) Bromine atoms are larger and this makes the formation of induced dipole-induced dipole attractions more favorable. C) The smaller chlorine molecules are able to pack together in a tighter physical orientation. D) The bromine ions are held together by ionic bonds.

B) Bromine atoms are larger and this makes the formation of induced dipole-induced dipole attractions more favorable.

Which of the following molecules would you expect to be the least attracted to a Na+ ion? A) H-F B) H3C-CH3 C) Cl2CH2 D) F- E) HO-

B) H3C-CH3

Which of the following elements will most likely form an ion with a +2 charge? A) Na B) Mg C) Ne D) Si E) Cl

B) Mg

Which should be larger, the potassium atom, K, or the potassium ion, K⁺? A) The potassium ion, K⁺ is larger since charging an atom always makes it larger. B) The potassium atom, K, with an additional shell of electrons is larger. C) The potassium ion, K⁺ is larger since it has an extra electron which increases its size. D) The potassium atom and the potassium ion are exactly the same size and only differ in charge.

B) The potassium atom, K, with an additional shell of electrons is larger.

How many valence electrons does gallium (Ga, atomic no. = 31) have? A) 1 B) 6 C) 3 D) 31

C) 3

Which of the following elements will most likely not form an ion at all? A) Na B) O C) Ar D) Mg E) Br

C) Ar

How do the electron-dot structures of elements in the same group in the periodic table compare with one another? A) The structures differ by exactly two electrons between vertically consecutive elements. B) The number of valence shell electrons increases by one for each element from the top to the bottom of the group. C) Elements of the same group have the same number of valence electrons. D) The number of electrons in the electron-dot-structure will equal the group number for each element of the group.

C) Elements of the same group have the same number of valence electrons.

Does an ionic bond have a dipole? A) No, dipoles are only found in covalent compounds. B) No, but the electrical charges are relatively strong. C) Yes, the ionic bond is an example of a very strong dipole. D) Yes, but for ionic compounds they are referred to as monopoles.

C) Yes, the ionic bond is an example of a very strong dipole.

Which of the following would be an ion with a double positive charge? A) an Mg atom that gains two electrons B) an Mg atom that gains one electron C) an Mg atom that loses two electrons D) an Mg atom that loses one electron

C) an Mg atom that loses two electrons

Which of the following best describes ionic bonding? A) two atoms sharing a set of electrons B) two atoms exchanging a set of electrons C) one atom giving up some of its electrons to another atom D) when two elements with same charge are held together by electrostatic forces

C) one atom giving up some of its electrons to another atom

How is it possible for a neutral molecule, such as water, to form an ion? A) It can combine with a hydrogen ion to form a positively charged species. B) It can combine with a chloride ion to form a negatively charged species. C) It can lose a hydrogen ion to form a negatively charged species. D) Both A and C are ways that a neutral molecule can form an ion.

D) Both A and C are ways that a neutral molecule can form an ion: A) It can combine with a hydrogen ion to form a positively charged species. C) It can lose a hydrogen ion to form a negatively charged species.

An individual carbon-oxygen bond is polar. Yet carbon dioxide, CO2, which has two carbon-oxygen bonds, is nonpolar because A) the molecule has an even number of electrons. B) it has a greater symmetry. C) the electron-pulls of the two oxygen atoms are equal and opposite. D) Both B and C

D) Both B and C : B) it has a greater symmetry. C) the electron-pulls of the two oxygen atoms are equal and opposite.

Which of the following bonds would be the least polar? A) C-F B) C-O C) C-Cl D) C-H

D) C-H

Which of the following would have the highest boiling point? A) C6H14 B) C8H18 C) C10H22 D) C12H26

D) C12H26

Which of the following has the greatest number of nonbonding pairs of electrons? A) C B) H C) He D) F E) S

D) F

Why doesn't the sodium atom gain seven electrons so that its third shell becomes the filled outermost shell? A) It would be too difficult for another atom to lose seven electrons. B) Only six additional electrons are required to fill the outermost shell of sodium. C) In gaining seven more electrons, sodium's fourth outer shell becomes filled. D) Sodium's nuclear charge is not strong enough to hold that many more electrons.

D) Sodium's nuclear charge is not strong enough to hold that many more electrons.

How is the number of unpaired valence electrons in an atom related to the number of bonds that the atom can form? A) There is no defined relationship between the number of unpaired valence electrons and number of bonds that the atom can form. B) The number of unpaired valence electrons in an atom is one-half the number of bonds that the atom can form. C) The number of unpaired valence electrons in an atom is twice the number of bonds that the atom can form. D) The number of unpaired valence electrons in an atom is the same as the number of bonds that the atom can form.

D) The number of unpaired valence electrons in an atom is the same as the number of bonds that the atom can form.

Water, H2O, and methane, CH4, have about the same mass and differ by only one type of atom. Why is the boiling point of water so much higher than that of methane? A) The water molecule is less symmetrical than is the methane molecule. B) The oxygen of a water molecule has two lone pairs of electrons. C) The electronegativity difference between oxygen and hydrogen is greater than the electronegativity difference between carbon and hydrogen. D) all of the above

D) all of the above: A) The water molecule is less symmetrical than is the methane molecule. B) The oxygen of a water molecule has two lone pairs of electrons. C) The electronegativity difference between oxygen and hydrogen is greater than the electronegativity difference between carbon and hydrogen.

Plastic wrap is made of nonpolar molecules and is able to stick well to polar surfaces, such as glass, by way of dipole/induced dipole molecular attractions. How is it that plastic wrap also sticks to itself so well? A) by way of dipole-dipole molecular attractions B) by way of dipole-induced dipole molecular attractions C) Ions are formed as the plastic rubs against itself. D) by way of induced dipole-induced dipole molecular attractions

D) by way of induced dipole-induced dipole molecular attractions

Classify the following bonds as ionic, covalent, or metallic (O, atomic number 8; F, atomic number 9; Na, atomic number 11; Cl, atomic number 17). O with F Ca with Cl Na with Na A) covalent, ionic, covalent B) ionic, covalent, metallic C) metallic, ionic, covalent D) covalent, ionic, metallic

D) covalent, ionic, metallic

The neon atom tends NOT to gain any additional electrons because A) its nuclear charge is not great enough. B) that would result in a positive ion. C) of the repulsions they would experience with electrons in the same shell. D) there is no more room available in its outermost occupied shell

D) there is no more room available in its outermost occupied shell

What does the line in the following example actually represent? H—H A) a shared pair of electrons B) a covalent bond C) an ionic bond D) a pair of nonbonding electrons E) A and B

E) A and B: A) a shared pair of electrons B) a covalent bond

Which of the following is the weakest? A) A chemical bond B) An ion-dipole attraction C) A dipole-dipole attraction D) A dipole-induced dipole attraction E) An induced dipole-induced dipole attraction

E) An induced dipole-induced dipole attraction

Which of the following elements will most likely form an ion with a -1 charge? A) Na B) S C) Ne D) Mg E) Cl

E) Cl

Which of the following statements describes a polar molecule? A) The electrons in the molecule are distributed evenly throughout the molecule. B) The molecules are usually not attracted to one another very strongly. C) Polar molecules have the weakest intermolecular interactions with ionic compounds. D) The molecules have a high degree of symmetry. E) None of these statements describe polar molecules.

E) None of these statements describe polar molecules.

Which of the following elements has six valence electrons? A) Be B) B C) C D) N E) O

E) O