chem exam 2
Write the ground state electron configuration of Ti4+
1s^2 2s^2 2p^6 3s^2 3p^6
Write the ground state electron configuration of Zn2+
1s^2 2s^2 2p^6 3s^2 3p^6 3d^10
Draw the Lewis structure of CH2CCH2 and then choose the appropriate set of paid hybridization states for the three central atoms. Your answer choice is independent of the orientation of your drawn structure. A) sp^2/sp/sp^2 B) sp^2/sp^2/sp^3 C) sp^3/sp^2/sp D) sp^2/sp^2/sp^2 E) sp/sp^3/sp^3
A
Draw the lewis structure of BCl3 and then choose the appropriate number of valence electrons on the central atom. A) 6 B) 8 C) 9 D)7 E) 10
A
When an atom gains an electron its radius... a) increases b) decreases c) stays the same
A) increases
Ions are describes as ... if they have the same number of electrons A) Isoelectronic B) Isoprotonic C) Isoneutronic D) Isotopes E) Orbitals
A)Isoelectronic Ions are described as isoelectronic when they have the same number of electrons
Which of the following is not an example of a covalent bond? A) N-N B)Mg-N C)N-O D) H-H
B- typically a nonmetal bonded to a nonmetal is a covalent bond
Write the chemical formula for carbon dioxide
CO2
Write the chemical formula for cadmium sulfide
CdS
Draw the Lewis structure of SOCl4 (with minimized formal charges) and then determine the hybridization of the central atom a) sp^3 b)sp c)sp^5 d) sp^3d e) sp^4
D
Draw the Lewis structure of SeF6 and then determine its electron domain and molecular geometries. A) Pentagonal/ octahedral B) Planar/ trigonal planar C) square/ trigonal bipyramidal D) Octahedral/octahedral E) trigonal bipyramidal/ planar
D
Write the chemical formula for sulfuric acid
H2SO4
Write the formula for hydroponic acid
HI
Write the chemical formula for Indium (III) Phosphide
InP
Provide the correct IUPAC name for FePO4*2H2O
Iron (III) phosphate dihydrate
Write the chemical formula for lithium oxide
Li2O
Provide the IUPAC name for Ni3(PO4)2
Nickel (II) Phosphate
Provide the IUPAC name for Ni(No2)2
Nickel (II) nitrite
When an atom loses an electron, its radius a) increases b) decreases c) stays the same
b) decreases
Provide the IUPAC name for BaCl2
barium chloride
Provide the correct IUPAC name for Bal2 X 2H20
barium iodide dihydrate
Draw the lewis structure of O2 and then determine if the molecule is polar or nonpolar
non polar
Provide the IUPAC name for H3PO4
phosphoric acid
Provide the correct IUPAC name for H3PO3(aq)
phosphorous acid
Provide the IUPAC name for PCl3
phosphorus trichloride
Write the ground state electron configuration of O2-
1s^2 2s^2 2p^6
Write the ground state electron configuration of Cr3+
1s^2 2s^2 2p^6 3s^2 3p^6 3d^3
Write the ground state electron configuration of Ca^2+
1s^2 2s^22p^63s^23p^6
Which of the following ranks these isoelectronic species in order of increasing atomic radii A) Al3+<Mg2+<Ne<F-<O2- B)O2-<F-<Ne<Mg^2+<Al3+ C)Al3+<Mg2+<O2-<F-<Ne D) Ne<F<O2-<Mg2+<Al3+ E)Mg2+<Al3+<Ne<F-<O2-
A) Al3+<Mg2+<Ne<F-<O2- In a series of isoelectronic ions, cations are smaller than anions. The larger the positive charge, the smaller the radius. The larger the negative charge, the larger the radius. A neutral atom is in the middle.
Which one of the following is the least electronegative atoms? A) Na B) Cl C) P D)Al
A) Na - electronegativity decreases as you move right to left and increases as you move left to right
Which of the following is an example of an ionic bond? A) K-F B) C-H C) Kr-H D) C-F
A- (K-f) is an ionic bond because the difference in electronegativity is greater than 1.5 and it is between a metal and a nonmetal
Determine the number of valence electrons in chlorite (ClO2-) and then draw the corresponding Lewis structure (by following the octet rule on all atoms) A) 24 B)20 C)19 D)18 E)21
B
Draw the lewis structure of Ozone (O3) and then determine its electron domain and molecular geometries. A) planar/ trigonal planar B) Trigonal planar/ bet (120 degrees) C) trigonal/ trigonal planar D) planar/ trigonal E) Pyramidal/ pyramidal
B
Draw the lewis structure of PF3 and then determine the number of nonbonding electron pairs on the central atom A) 0 B)1 C) 2 D)4 E) 6
B
Which one of the following is the correct set of Lewis Symbols for CaCl2?
B
Which one of the following statements best describes electronegativity in atoms? A) Electronegativity is what happens when an atoms gains an electrons to become an anion B)Electronegativity is the attraction an element's nucleus has for the electrons in a chemical bond C) Electronegativity is the energy lost when an atom gains an electron D) Electronegativity is the energy absorbed when an atoms loses an electron
B- Electronegativity is the attraction an element's nucleus has for the electrons in a chemical bond
Which of the following is the correct Lewis Structure for a neutral atom of F
B- a neutral atom of F has 7 valence electrons
Which atoms in the C-Br bond has a partial negative charge (delta-)? A) C B) Br C) Both D) Neither
Br- partial charges are determined by the relative electronegativities of the atoms in a bond; the more electronegative atom, which is Br, has a partial negative charge
Draw the Lewis Structure of CBr4 and then determine its electron domain and molecular geometries: A) trigonal/planar B) linear/ trigonal pyramidal C) tetrahedral/tetrahedral D) Planar/trigonal E) Planar/ tetrahedral
C
Which of the following radii comparisons is correct? A)N3-<N B)Ti4+>Ti3+ C)In3+<In+ D) C4+>C^4- E)As3-<As3+
C) In3+<In+ Cations are always smaller than the neutral atom from which it derived. Anions are always larger than the neutral atom from which it is derived. Therefore, the smaller ion in a pair will be the one with fewer electrons.
A bond dissociation energy is A) the energy required to remove an electron from an atom B) the energy released when an ionic compound dissociates in water C) the energy required to break a covalent bond into two fragments each with one electron from the bond D) the energy produced in a chemical reaction that breaks chemical bonds
C- A bond dissociation energy is the energy required to break a covalent into two fragments each with one electron from the original bond
Write the chemical formula for Copper(I) thiocyanate
CuSCN
Draw the lewis structure of CH3OH. Then determine the hybridization of the oxygen atom. A) s B) sp C) sp^2 D)sp^3
D
Draw the lewis structure of SF4 and then determine its electron domain and molecular geometries A) trigonal planar/ tetrahedral B) Trigonal/trigonal planar C) pyramidal/pyramidal D) Trigonal bipyramidal/ see-saw E) Trigonal/ bet (109.5 degrees)
D
Which of the following elements is the most electropositive? A) F B)Cl C) O D) P E) S
D- Phosphorous is the least electronegative of this group and therefore is the most electropositive
How many electrons are shared between two atoms in a triple bond? A)2 B)3 C)4 D)6
D- Two electrons are shared between two atoms in an individual bond, therefore in a triple bond 2X3=6 electrons are shared
The Lewis structure of N2S is shown on the left below with numbers on the corresponding atoms. Choose the correct set of formal charges of the atoms in ascending order of atom number. A) #1=-2, #2=+1, #3=+1 B) #1= +1, #2=-1, #3=0 C) #1=-1, #2=+1, #3=0 D) #1=0, #2=0, #3=0 E) #1=0, #2=+1, #3=-1
E
Draw the Lewis structure of XeF4, and then determine if the molecule is polar or non polar
Nonpolar
A lewis structure for an isomer of C2H2F2 is shown below. Based on this structure, determine if the molecule is polar or nonpolar.
Nonpolar: the dipole from the fluorines on opposite side of the place cancel each other out and cause no net dipole for the molecule
Write the chemical formula for tetraphosphorus decoxide
P4O10
Write the chemical formula for lead(IV) permanganate
Pb(MnO4)4
Provide the correct IUPAC name for H3PO4(aq)
Phosphoric acid
Provide the correct IUPAC name for Cl2O7
dichloride heptoxide
Identify the correct dipole for the C-Cl bond in the lewis structure of chloroform using symbols delta+ and delta-. A) (Delta+) C-Cl(Delta-) B)(Delta-)C-Cl(Delta+) C) (Delta -)C-Cl(Delta-) D) (Delta +)C- Cl(delta+)
A- Partial charges are determined by the relative electronegativities of the atoms in a bond; the more electronegative atom,Cl, has a partial negative charge and the less electronegative atom, C, has a partial positive charge (Delta+)C-Cl(Delta-)
A Lewis structure for SO3 is shown below on the left. Predict whether bonding angle A will be equal to, greater than, or less than the ideal bonding angle according to the VSEPR model. a) equal b)greater than c) less than
A- consider the additional electronic repulsions provided by the lone pairs and double bonds on the structure. This will result in Bond Angle A being equal to the ideal bonding angle according to the VSEPR model
The overall charge is -2 in the Lewis Structure shown below. Choose the possible identity or identities of the central atom. A) C,Si, or Ge B) S or Se C) P or As D) N, P, or As E) Cl, Br, or I
B
A lattice dissociation enthalpy (lattice energy) is A) the energy required to break a chemical bond B) the amount of energy that must be supplied to break an ionic solid solid into its individual gaseous ions C) the difference in ionization energy and electron affinity of the anion and cation D) the energy required to convert a substance from a solid to a gaseous state
B- A lattice dissociation enthalpy (lattice energy) is the amount of energy that must be supplied to break an ionic solid into its individual gaseous ions
Which atom in the O-P single bond has a partial negative charge (deta-)? A) P B) O C) Both D) Neither
B- Partial charges are determined by the relative electronegativities of the atoms in a bond; the more electronegative atom, which is O, has a partial negative charge
In a Polar covalent bond, A) both atoms in the bond have the same level of electronegativity B) one atom in the bond must have higher electronegativity C) one atom must be a H atom D) both atoms in the bond must be metals
B- Polar bonds occur between two nonmetals and have a difference in electronegativities of the atoms
Which structures below are plausible resonance contributors for H2NNO2? Assume the connectivity is as written A) I and II B) I and III C) I and IV D) II and III E)II and IV
B- Structures I and III are both plausible resonance contributors of rH2NNO2. In a resonance structure, pi electrons and non-bonding electrons can be placed in different locations, but the electrons in sigma bonds must remain the same. Period II atoms, such as nitrogen and oxygen, want an octet, but they cannot exceed an octet
Which of the following is the correct Lewis symbol for the calcium ion?
B- a neutral atom of Ca has two valence electrons. In order to be isoelectronic with a noble gas, calcium will lose 2 valence electrons
Single, double, or triple covalent bonds in a carbon atom are formed from A) inner shell electrons B) valence electrons C) both inner shell and valence electrons
B- single, double, or triple covalent bonds in a carbon atom are formed from valence electrons
A Lewis structure for IF4+ is shown below on the left. Predict whether bonding angle A will be equal to, greater than, or less than the ideal bonding angle according to the VSEPR model A) Equal B) Greater Than C) Less than
C- Consider the additional electronic repulsions provided by the lone pairs on the structure. This will result in Bond Angle A being less than the ideal bonding angle according to the VSEPR model.
Which has the incorrect name-formula combination A) Iron (III) fluoride- FeF3 B) Cobalt (II) oxide- CoO C) Copper (I) sulfide- CuS D) Chromium (II) bromide- CrBr2
C- Consider the charge of the ions to make sure the charges are balanced. For the transition metals, the charge is indicated in the name with a Roman numeral in parentheses. For example, copper (I) sulfide indicates that the copper ion has a +1 charge. Sulfide has -2 charge. The formula for copper (I) sulfide would be Cu2S
In a covalent bond A) two atoms enhance electrons and the ions are attracted to one another B) two ions come together and form a crystal lattice C) two atoms share valence electrons and those shared electrons from the chemical bond D) two elements react and form a new compound
C- In a covalent bond, two atoms share valence electrons and those shared electrons form the chemical bond
Which of the following is not a valid lewis symbol?
D- count the number of valence electrons for each atom. Bromine only has 7 valence electrons and this structure shows it with 8.
Draw the lewis structure of NO2 and then choose the appropriate formal charge for the central atom A) -2 B) -1 C) 0 D) +1 E) +2
D- formal charge= v.e. -lines-dots (add charges together they should equal charge on atom)
Based on their positions in the periodic table, which of the following bonds is the most polar? A)C-O B)C-N C)C-B D)C-F
D- polar bonds occur between two nonmetals and have a difference in electronegativites of the atoms. The further apart two atoms are in the same period, the greater the polarity of the bond
Identify the overall molecular dipole moment of water using a vector arrow A) I B) II C) III D) IV
D- the overall molecular dipole can be determined by summing the vectors from the individual bond dipoles. Begin by designating the individual O-H bond dipoles, which are determined by the relative electronegativites of the atoms in a bond. Oxygen is more electronegative than hydrogen, therefore the vector arrow for each O-H bond dipole points along the bond axis, toward O. Then, sum the two O-H bond vectors to give the overall molecular dipole moment, shown as a vector arrow pointed up
