Cannot be determined from this information. A. Incorrect. The electronegativity difference isn t great enough to be an ionic bond.

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1 AP Chemistry - Problem Drill 14: Chemical Bonding Theories No. 1 of What type of bond is H O? (A) (B) (C) (D) (E) Ionic Non-polar Covalent Polar Covalent Metallic Cannot be determined from this information. The electronegativity difference isn t great enough to be an ionic bond. The electronegativity difference is too great to be a non-polar covalent bond. C. Correct. The electronegativity difference is in the polar covalent zone. Two non-metals don t form a metallic bond. E. Incorrect. Look up the electronegativity of the two atoms and determine how different they are to determine bond type. Electronegativity of H = 2.1 Electronegativity of O = 3.5 Electronegativity difference = 1.4 The H O bond is within the polar covalent bond region. The correct answer is (C).

2 No. 2 of How many sigma and pi bonds are in the following? Sigma Pi (A) 12 2 (B) 8 2 (C) 8 4 (D) 10 2 (E) 12 0 Sigma bonds are the first bonds between each pair of atoms. All other bonds are pi bonds. Sigma bonds are the first bonds between each pair of atoms. All other bonds are pi bonds. Sigma bonds are the first bonds between each pair of atoms. All other bonds are pi bonds. D. Correct. Sigma bonds are the first bonds between each pair of atoms. All other bonds are pi bonds. E. Incorrect. Sigma bonds are the first bonds between each pair of atoms. All other bonds are pi bonds. Sigma bonds are the first bonds between each pair of atoms. Pi bonds are the 2 nd and 3 rd bond between a pair of atoms. There are 10 first bonds. There are 2 second bonds. Sigma bonds = 10; Pi bonds = 2 The correct answer is (D).

3 No. 3 of What type of hybridization does the red atom have? (A) sp (B) sp 2 (C) sp 3 (D) sp 3 d (E) sp 3 d 2 A. Correct. This atom has 2 sigma bonds and 2 pi bonds with 2 atoms/lone-pairs bonded to it in a linear geometry; hence it is indeed sp hybridization. The sp 2 should have 3 atoms/lone-pairs bonded in a trigonal planar geometry. However, this atom has only 2 atoms bonded in a linear geometry. The sp 3 should have 4 atoms/lone-pairs bonded in a tetrahedral geometry. However, this atom has only 2 atoms bonded in a linear geometry. The sp 3 d should have 5 atoms/lone-pairs bonded to a central atom in a trigonal bipyramidal geometry. The sp 3 d 2 should have 6 atoms/lone-pairs bonded to a central atom in an octahedral geometry. Hybridization sp: 2 atoms/lone-pairs bonded to the C with a linear geometry. Hybridization sp 2 : 3 atoms/lone-pairs bonded to the C with a trigonal planar geometry. Hybridization sp 3 : 4 atoms/lone-pairs bonded to the C with a tetrahedral geometry. Hybridization sp 3 d: 5 atoms/lone-pairs bonded to the C with a trigonal bipyramidal geometry. Hybridization sp 3 d 2 : 6 atoms/lone-pairs bonded to the C with an octahedral geometry. An atom with 4 sigma bonds = sp 3. An atom with 3 sigma bonds = sp 2. An atom with 2 sigma bonds (and 2 pi bonds) = sp This is sp hybridization. Answer: (A) sp

4 No. 4 of Which type of compound is the most likely to be soluble in water? (A) Ionic (B) Non-polar covalent (C) Polar covalent (D) Metallic (E) None of the above A. Correct. Ionic bonds form similar intermolecular forces with water and therefore are the most likely to be soluble. Non-polar covalent molecules are not likely to be soluble in water as they only form London Dispersion Forces. Although some polar covalent molecules are soluble, there is another choice that is more likely to be soluble. Metallic compounds are not likely to be soluble in water. One of those types is most likely to dissolve in water. Some polar covalent compounds do dissolve in water, but ionic compounds are more likely to dissolve in water. The correct answer is (A).

5 No. 5 of Which compound has the greatest ionic character? (A) CsF (B) RbF (C) NaF (D) LiF (E) Cannot be determined from this information. A. Correct. The greater the difference in electronegativity, the greater the ionic character. The greater the difference in electronegativity, the greater the ionic character. The greater the difference in electronegativity, the greater the ionic character. The greater the difference in electronegativity, the greater the ionic character. E. Incorrect. The greater the difference in electronegativity, the greater the ionic character. The greater the difference in electronegativity, the greater the ionic character. In general, the farther 2 elements are from each other on the periodic table, the greater the difference in electronegativities. Cs & F are the farthest apart as they can get. The correct answer is (A).

6 No. 6 of Which scenario would result in the greatest lattice energy? (A) Low charge and small radii. (B) Low charge and large radii. (C) Higher charge and small radii. (D) Higher charge and larger radii. (E) All ionic compounds have the same lattice energy. C. Correct. Therefore, the higher the charge and the smaller the radii, the greater the lattice energy. The correct answer is (C).

7 No. 7 of The following pictures are an example of:..... O.. N. O O O = N.. O O O N = O O. (A) isomers (B) resonance structures (C) isotopes (D) lattice structures (E) cations Isomers have the same chemical formula but different molecular structure. B. Correct. The structures are the same except for the position of the double bond between nitrogen & oxygen. Isotopes are two atoms of the same element with a different number of neutrons. Lattice structures are found in ionic compounds. Cations are positively charged ions these are anions. They all have the same structure but the double bonds are in different locations. These are resonance structures. The correct answer is (B).

8 No. 8 of A double bond consists of: (A) 1 sigma bond & 1 pi bond (B) 2 sigma bonds (C) 2 pi bonds (D) 1 pi bond only (E) 1 sigma bond only A. Correct. The correct answer is (A).

9 No. 9 of CH 4 is what type of compound? (A) Ionic (B) Polar covalent (C) Non-polar covalent (D) Metallic (E) None of the above Ionic bonds are formed between metals and non-metals. This electronegativity difference is not great enough to be a polar covalent bond. C. Correct. The electronegativity difference is low enough to be a non-polar covalent bond. Non-polar molecules do not form metallic bonds. Look closely there is a correct answer. Carbon & hydrogen atoms always form non-polar covalent bonds. If the bonds are all non-polar covalent and there aren t any lone pairs on the central atom, the compound is non-polar as well. The correct answer is (C).

10 No. 10 of Metallic compounds tend to be. (A) soluble in water (B) brittle (C) malleable (D) liquids (E) semiconductors Metallic compounds are not soluble in water. Metallic compounds can be shaped easily they are not brittle. C. Correct. Metallic compounds can be hammered into a sheet (they are malleable). Metals tend to be solids. Metals are conductors, not semiconductors. Metallic compounds do not dissolve in water. They are malleable, ductile (which is the opposite of brittle), rarely liquids (at standard temperature and pressure), and are conductors instead of semiconductors. The correct answer is (C).