1. Which Formula Represents an Ionic Compound? (A) H2O (B) NH3 (C) Nacl (D) Ccl4

UNIT 6 TEST (ADV.)

1. Which formula represents an ionic compound?
(A) H2O (B) NH3 (C) NaCl (D) CCl4

2. Which formula represents a tetrahedral molecule?
(A) CH4 (B) HBr (C) CaCl2 (D) Br2

3. Which formula represents a polar molecule containing polar covalent bonds?
(A) H2O (B) NaCl (C) CO2 (D) Cl2

*4. Which substance exhibits metallic bonding?
(A) Ar (B) SiO2 (C) Au (D) CO2

5. The bonding in NH3 is most similar to the bonding in
(A) H2O (B) MgO (C) NaCl (D) KF

6. The bonds present in silicon carbide (SiC) are
(A) ionic (B) polar covalent (C) metallic (D) nonpolar covalent

*7. Which element could be considered malleable?
(A) gold (B) hydrogen (C) sulfur (D) radon

8. Why is NH3 classified as a polar molecule?
(A) NH3 is a gas.
(B) The bonds between nitrogen and hydrogen are nonpolar.
(C) Nitrogen and hydrogen are both nonmetals.
(D) NH3 molecules have unshared electron pairs around the central atom.

9. Which molecule contains a nonpolar covalent bond?
(A) HCl (B) CO2 (C) F2 (D) NH3

10. An ionic bond forms between atoms of
(A) I and Cl (B) P and Cl (C) K and Cl (D) H and Cl

11. Which compound contains an alkali metal and a halogen?
(A) CaCl2 (B) RbCl (C) CaS (D) Rb2S

12. A characteristic of ionic solids is that they
(A) have high melting points (B) have low boiling points
(C) conduct electricity (D) are noncrystalline

*13. Mobile electrons are a distinguishing characteristic of
(A) an ionic bond (B) a metallic bond
(C) an electrovalent bond (D) a covalent bond

14. Given the equation: I + I --> I2
As the atoms of the iodine react to form molecules of iodine, the stability of the iodine
(A) increases (B) decreases (C) remains the same

*15. What type of bond is found in copper metal?
(A) ionic (B) covalent (C) metallic (D) London dispersion

16. Which molecule contains a nonpolar covalent bond?
(A)(B) (C) (D)

17. Electrons in the outermost energy level of an atom are called
(A) polar electrons (B) metallic electrons (C) valence electrons (D) transfer electrons

18. The smallest unit of an ionic compound is called a(n)
(A) atom (B) molecule (C) formula unit (D) polyatomic ion

19. Which formula represents an ionic compound?
(A) H2O (B) NaCl (C) NH3 (D) CCl4

20. What type of bonding can be found in the compound HBr?
(A) ionic (B) metallic (C) nonpolar covalent (D) polar covalent

21. In many compounds, atoms of main group elements form bonds so that the number of valence electrons in
each atom is
(A) 2 (B) 6 (C) 8 (D) 10

22. In which of these compounds is the bond between the atoms NOT a nonpolar covalent bond?
(A) Cl2 (B) H2 (C) HCl (D) O2

23. Which compound is ionic?
(A) HCl (B) CaCl2 (C) SO2 (D) N2O

24. Atoms of which elements have the strongest attraction for electrons?
(A) Al (B) Cl (C) Si (D) Na

25. The forces of attraction that exist between nonpolar molecules are called
(A) London dispersion (B) ionic (C) covalent (D) dipole-dipole

26. A pure substance melts at 38 oC and does not conduct electricity in either the solid or liquid phase. The
substance is classified as
(A) ionic (B) metallic (C) electrovalent (D) molecular

27. As a chemical bond forms between two atoms, the potential energy of the atoms
(A) increases (B) decreases (C) remains the same

28. An atom that loses or gains one or more electrons becomes
(A) an ion (B) an isotope (C) a molecule (D) an electrolyte

29. Which is a characteristic of ionic solids?
(A) They conduct electricity. (B) They are formed by the sharing of electrons.
(C) They have high melting points. (D) They usually exist as gases or liquids.

30. Which kind of bond is formed when two atoms share electrons to form a molecule?
(A) ionic (B) metallic (C) electrovalent (D) covalent

31. Which type of bonding is usually exhibited when the electronegativity difference between the two atoms is
1.2?
(A) ionic (B) metallic (C) polar covalent (D) nonpolar covalent

32. Which term applies to the attraction between nonpolar molecules and between noble gas atoms?
(A) hydrogen bonding (B) ionic bonding (C) covalent bonding (D) London dispersion forces

33. Hydrogen bonds are strongest between the molecules of
(A) HF (B) HCl (C) HBr (D) HI

34. Which elements have the most similar chemical properties?
(A) K and Na (B) K and Ca (C) K and Cl (D) K and S

35. Which is the electron configuration of an atom of a Period 3 element?
(A) 1s2 2s1 (B) 1s2 2s2 2p3 (C) 1s2 2s2 2p1 (D) 1s2 2s2 2p6 3s1

36. An atom of an element has the electron configuration of 1s2 2s2 2p2. What is the total number of valence
electrons in this atom?
(A) 6 (B) 2 (C) 5 (D) 4

37. In general, the chemical properties of elements, their oxidation number, and their bond formation are due to
(A) the electrons in the outer shell (B) the polar electrons (C) the charge on the nucleus
(D) the neutrons in the nucleus (E) none of these

38. Which substance has bonds of greatest ionic character?
(A) gaseous hydrogen, H2 (B) lithium fluoride, LiF
(C) xenon tetrafluoride, XeF4 (D) gaseous fluorine, F2

39. When electrons are equally shared, a bond is said to be
(A) nonpolar covalent (B) ionic (C) polar covalent (D) not possible

40. When the electronegativity difference between two atoms is 2, what type of bond could be predicted?
(A) ionic (B) covalent (C) metallic (D) hydrogen

41. The oxidation number of neon is
(A) 0 (B) -2nbssp; (C) -4nbssp; (D) -6nbssp; (E) -8

42. Which one of the following statements about chemical bonding is NOT true? A chemical bond forms
between two atoms
(A) only when equal sharing of the bonding electrons results
(B) when the attractive forces are greater than the repulsive forces between the atoms
(C) because a lowering of energy results from such bond formation
(D) when empty or half-filled orbitals permit electrons to position themselves between two nuclei
(E) because the molecule formed is more stable than the individual atoms

43. The type of bond that is formed as a result of the transfer of electrons is called
(A) metallic (B) intermolecular (C) ionic (D) covalent