chem 2 exam review

Consider the electron configuration for fluorine (F) and the electron configuration for chlorine (Cl). What is different about the valence electrons in these two atoms? I.There are different numbers of valence electrons. II.The valence electrons have different energies. III.The valence electrons are in different types of orbitals (s, p, d, f). IV.The valence electrons are in different size orbitals. A. 1 only B. 1 and 3 C. 2 only D. 4 only E. 2 and 4

E. 2 and 4

Thomson's cathode ray tube experiment proved false what part of Dalton's atomic theory? a. All atoms are indivisible and indestructible. b. All atoms of a given element are identical. c. All matter is made of atoms. d. Compounds are formed from the combination of two or more elements. e. Chemical reactions are rearrangements of atoms.

a. All atoms are indivisible and indestructible.

Use the data table for the first eight ionization energies of a particular element shown below to predict and explain which element you would expect to show this trend in successive ionization energies. I. Fluorine II. Oxygen Because III. core electrons are more strongly attracted to the nucleus than valence electrons. IV. valence electrons release more energy when they are removed from the atom. a. I and III b. II and III c. I and IV d. II and IV

b. 2 and 3

The diagram below is for two subatomic particles. What does the curve show? I. The potential energy decreases as the objects get closer together. II. The potential energy increases as the objects get closer together. Which two subatomic particles could this curve represent? III. Two neutrons IV. Two electrons V. One proton and one electron a. II and III b. II and IV c. I and IV d. II and V e. I and III

b. 2 and 4

o the right is the molecular orbital diagram for a diatomic molecule. Which molecule is this and how many bonds form between the atoms? molecule #bonds a. F2 2 b. F2 1 c. Cl2 1 d. Cl2 2 e. O2 3

b. F2 and 1

Which do you predict has the higher boiling point and why? I. Cl2 II. Ar Because::: II. When this substance boils, covalent bonds are overcome. IV. When this substance boils, LDFs are overcome. V. Covalent bonds are stronger than LDFs. VI. The strength of the LDFs depends on the size of the electron cloud. a. I, III, V b. I, IV, VI c. II, IV, VI d. I, III, IV, V e. II, III, V

b. I, IV, VI

Which of the following contain(s) atoms? a. heat b. air c. energy d. light e. all of the above

b. air

The molecular orbital diagram to the right shows the electron configurations for two atoms that have the same number of protons. Fill in the molecular orbitals with the electrons provided. From the answers below, what molecule or ion will be formed? a. O2 b. O2- c. F2- d. OF e. F2

b. o2-

Which of the following elements has the largest atomic radius? a. Nitrogen b. Phosphorus c. Oxygen d. Sulfur e. Chlorine

b. phosphorus

Consider the following statements about ionization energy. Which ones are true? I. It takes energy from the surroundings to remove an electron to make an ion. II. It takes less energy to remove a second electron to make a 2+ ion vs. making the ion 1+ III. It takes roughly the same amount of energy to remove the sixth electron from Nitrogen as it does the sixth in Oxygen. a. I, II, and III b. I and II c. I only d. II and III e. I and III

c. 1 only

If we have an oxygen atom, it will typically form a I. -1 ion II. -2 ion. Because III. It has six valence electrons and it needs the additional electron(s) to fill its p orbitals. IV. It has four valence electrons and it needs the additional electron(s) to fill its p orbitals. V. It will promote s orbital electrons to fill the p orbitals. a. I and III b. I and IV c. II and III d. II and IV e. II, IV, and V

c. 2 and 3

Which statements are true about the p orbital shown to the right? I. It can hold up to two electrons. II. It can hold up to six electrons. III. An electron in this orbital moves around the edge in a figure eight pattern. IV. An electron of a certain energy is highly likely to be found within the orbital, but we cannot say exactly where. a. I and III b. II and III c. I and IV d. II and IV e. I, II, III, and IV are all correct

c. I and IV

What is true considering the bonding of atoms in clusters? a. Atoms bound in small clusters (i.e. a few 100 atoms) behave the same as the bulk material (macro scale). b. Small gold nanoparticle clusters behave the same as larger ones. c. When atoms are bound in small clusters (i.e. nanoparticles) their behaviors are different because nanoscale behavior is different than macroscale. d. Atoms typically do not bond to the same type of atom to make a molecule. e. Both a and b are true.

c. When atoms are bound in small clusters (i.e. nanoparticles) their behaviors are different because nanoscale behavior is different than macroscale.

What is the evidence that supports the claim that light is a particle? a. When light shines on metal, a photon is absorbed and then emitted in many wavelengths to produce the characteristic shine of metal. b. Increasing the amplitude makes light appear brighter. c. When light shines on metal there is a threshold frequency, below which no electrons are ejected from a metal. d. Electrons produce an interference pattern. e. Electrons absorb certain photons of light to move to higher energy levels. The electrons can emit the photon to move back to the lower energy level

c. When light shines on metal there is a threshold frequency, below which no electrons are ejected from a metal.

Overlap in the atomic orbitals shown to the right will result in what type of bonding molecular orbital? a. s b. s* c. p d. p* e. These orbitals cannot combine to form a bonding MO.

c. p

According to molecular orbital theory, when atomic orbitals combine destructively: I. Electrons in anti-bonding molecular orbitals make the species less stable. II. Electrons in anti-bonding molecular orbitals make the species more stable. Because III. Anti-bonding molecular orbitals are lower energy than the atomic orbitals. IV. Anti-bonding molecular orbitals are higher energy than the atomic orbitals. a. I and III b. II and IV c. II and III d. I and IV

d. 1 and 4

What is the electron configuration of Mg+? a. 1s2 2s2 2p6 3s2 b. 1s2 2s2 2p6 c. 1s2 2s2 2p6 3s2 3p3 d. 1s2 2s2 2p6 3s1 e. 1s2 2s2 2p5

d. 1s2 2s2 2p6 3s1

How many core and valence electrons does one atom of iodine (I) have? a. 36 core and 17 valence b. 36 core and 7 valence c. 7 core and 36 valence d. 46 core and 7 valence e. 46 core and 17 valence

d. 46 core and 7 valence

Consider three isolated ions: Mg2+, O2- and Na+. Which is true about these ions? a. All of the ions are the same size. b. All of the ions have the same numbers of protons. c. All of the ions have the same electrostatic attraction between protons and electrons. d. All of these ions have the same number of electrons present. e. a and d

d. All of these ions have the same number of electrons present.

What is the best explanation for why metals are ductile? a. Valence electrons carry charge anywhere within molecular orbitals that span the metal. b. Photons are absorbed and re-emitted. c. Metallic bonds involve delocalized electrons whereas covalent bonds involve localized electrons. d. When the nuclei move relative to one another, the valence electrons act as a glue holding them together.

d. When the nuclei move relative to one another, the valence electrons act as a glue holding them together.

Consider the first ionization energy for two atoms: Nitrogen (N) and Oxygen (O). Which one has the higher ionization energy and why? I. Nitrogen. II. Oxygen Because III. It lies further to the right within the same row of the periodic table. IV. It is a smaller atom V. Electrostatic repulsion means it is harder to remove an electron from a singly occupied orbital vs. a doubly occupied one. a. I and III b. I and IV c. II and III and IV d. II and V e. I and V

e. 1 and 5

Atomic radius _______ from left to right across a row on the Periodic Table. I. increases II. decreases Because III. the number of electrons increases IV. the mass increases V. the relative attraction between the protons and the outer electrons increases a. I and IV b. I and V c. II and III d. II and IV e. II and V

e. 2 and 5

Two elements 1 and 2 are in the same row of the periodic table but not next to each other. Element 1 has a larger atomic radius than element 2, which of the following are most likely to be true about their relative ionization energies and why? I. Element 1 has a larger ionization energy II. Element 2 has a larger ionization energy III. They both have the same ionization energy Because IV. electrons in element 1 are more strongly attracted to the nucleus V. electrons in element 2 are more strongly attracted to the nucleus VI. electrons are being removed from the same quantum shell a. I and IV b. II and IV c. III and VI d. I and V e. II and V

e. 2 and 5

Molecular orbitals in metals... a. Overlap significantly to allow free electron movement through the system. b. Have a large gap between bonding and valence bands so that electrons cannot easily be promoted to higher energy levels. c. Are so numerous because each atom contributes its atomic orbitals to a large network. d. All of the above. e. Both a and c.

e. Both a and c.

Consider K+ and Cl-. Which do you predict is larger and why? a. K+ is larger because potassium (K) is farther to the left and farther down the periodic table than chlorine (Cl). b. K+ is larger because it contains more electrons so there are more electron-electron repulsions c. K+ and Cl- are the same size because they both contain the same number of electrons so there is the same amount of electron-electron repulsion. d. Cl- is larger because anions are always larger than cations. e. Cl- is larger because fewer protons are attracting the same number of electrons as K+

e. Cl- is larger because fewer protons are attracting the same number of electrons as K+