Unit 6 Test – Chemistry I
1. Which of the following has a bent shape?
(A) SF2
(B) SiCl4
(C) PH3
(D) CO2
2. A molecule with a trigonal pyramid shape will always be polar because
(A) trigonal pyramid molecules only live in Antarctica
(B) their surrounding atoms are never the same element
(C) there is always one unshared electron pair on the central atom
(D) there are three surrounding atoms and there is always space left at the top of the molecule
3. According to the VSEPR theory, an AB3 molecule is
(A) linear
(B) bent
(C) trigonal planar
4. An ionic bond forms between atoms of
(A) Cl and Cl (B) P and Cl
(C) K and Cl
(D) trigonal pyramid
(D) H and Cl
5. The bonding in NH3 is most similar to the bonding in
(A) MgO
(B) KF
(C) H2O
(D) NaCl
6. Which compound best illustrates ionic bonding?
(A) H2O
(B) CCl4
(C) MgCl2
(D) CO2
7. Separate, individual atoms of elements are ___ stable as when they are combined with other elements.
(A) more
(B) less
(C) equally as
8. Which kind of bond is formed when two atoms share electrons to form a molecule?
(A) ionic
(B) metallic
(C) electrovalent
(D) covalent
9. What shape are molecules that belong to classes AB2E and AB2E2?
(A) linear
(B) bent
(C) trigonal planar
(D) trigonal pyramid
10. The type of bond formed as a result of the transfer of electrons is called
(A) metallic
(B) ionic
(C) intermolecular
(D) covalent
11. Given the equation: I + I  I2
As the atoms of iodine react to form molecules of iodine, the stability of the iodine
(A) Increases
(B) decreases
(C) remains the same
12. Which type of bond is usually exhibited when the electronegativity difference between two atoms is
2.1?
(A) ionic
(B) metallic
(C) nonpolar covalent
(D) polar covalent
13. Which formula represents a tetrahedral molecule?
(A) HBr
(B) Br2
(C) CaCl2
(D) CH4
14. In which of these compounds is the bond between the atoms NOT a nonpolar covalent bond?
(A) Cl2
(B) H2
(C) O2
(D) CO2
15. Which electron dot formula represents a substance that contains a nonpolar covalent bond?
(A)
(B)
(C)
(D)
16. How many double bonds are there in the Lewis structure for nitrate, NO3-1?
(A) zero
(B) one
(C) two
(D) three
17. In potassium bicarbonate, KHCO3, the bonds are
(A) ionic only
(B) both ionic and covalent
(C) covalent only
(D) both ionic and metallic
18. Which of the following molecules contains a polar covalent bond?
(A)
(B)
(C)
19. The bond between a metal and a nonmetal is
(A) nonpolar covalent
(B) ionic
(D)
(C) polar covalent
20. Which combination of atoms can form a polar covalent bond?
(A) H and Br
(B) N and N
(C) H and H
(D) metallic
(D) Na and Br
21. If two covalently-bonded atoms are identical, the bond between them is
(A) nonpolar covalent
(B) ionic
(C) polar covalent
(D) metallic
22. What element would be the central atom when drawing the Lewis structure for the compound AsI3?
(A) As
(B) I
(C) 3
(D) I3
23. Once an atom has lost or gained electrons, it is
(A) an isotope
(B) an alloy
(C) a polyatomic ion
24. According to the VSEPR theory, the structure of the molecule SeH2 is
(A) linear
(B) bent
(C) trigonal planar
(D) an ion
(D) trigonal pyramid
25. In which compound have the electrons been transferred to the oxygen?
(A) Na2O
(B) N2O
(C) NO2
(D) CO
26. Which of the following has two shared pairs and two unshared pairs of electrons on its central atom?
(A) CH4
(B) H2O
(C) NH3
(D) HF
Tell which type of bonding each of the following describes. Mark (A) for ionic or (C) for covalent.
27. transfers electrons
28. occurs between nonmetals
29. shares electrons
30. occurs between a metal and a nonmetal
Get the answers to this test