Which of the following molecules is/are nonpolar?
H2S
O3
COS
C2H2
SO2
SiF4
PF3
HCN
NH3
CS2
HN3
SO3
CF4
BF3
H2O
N2O
AsH3
See your other post above.
To determine whether a molecule is nonpolar, we need to look at its molecular geometry and the polarity of its bonds.
1. H2S: This molecule has a bent shape due to the lone pairs on the sulfur atom. The S-H bonds are polar, but due to the molecular shape, the bond polarities cancel each other resulting in a nonpolar molecule.
2. O3: Ozone has a bent shape but it is a polar molecule due to the presence of a polar double bond between the central oxygen atom and the terminal oxygen atoms.
3. COS: Carbonyl sulfide is a linear molecule with polar C=O and C-S bonds. Since these bonds do not cancel each other, COS is a polar molecule.
4. C2H2: Acetylene has a linear shape, and the carbon-carbon triple bond is nonpolar. However, the carbon-hydrogen bonds are polar. Due to the opposing polarities of the bonds, C2H2 is a nonpolar molecule.
5. SO2: Sulfur dioxide has a bent shape with two polar S=O bonds. The bond polarities do not cancel each other, making it a polar molecule.
6. SiF4: Silicon tetrafluoride has a tetrahedral shape with four fluorine atoms bonded to the silicon atom. The bond dipoles cancel each other, resulting in a nonpolar molecule.
7. PF3: Phosphorus trifluoride has a trigonal pyramidal shape. The P-F bonds in PF3 are polar, but the presence of lone pair on phosphorus atom makes the molecule polar.
8. HCN: Hydrogen cyanide is a linear molecule. The C-H bond is polar, while the C-N bond is polar. The molecule is polar due to the opposing polarities of the bonds.
9. NH3: Ammonia has a trigonal pyramidal shape, with three polar N-H bonds. The bond polarities do not cancel each other, making NH3 a polar molecule.
10. CS2: Carbon disulfide has a linear shape. The C-S bonds are polar, but since the bond polarities cancel each other, CS2 is a nonpolar molecule.
11. HN3: Hydrazoic acid has a linear shape and the N-H bond is polar. This makes HN3 a polar molecule.
12. SO3: Sulfur trioxide has a trigonal planar shape and three polar S-O bonds. The bond polarities do not cancel each other, making SO3 a polar molecule.
13. CF4: Carbon tetrafluoride has a tetrahedral shape with four polar C-F bonds. However, the bond dipoles cancel each other, resulting in a nonpolar molecule.
14. BF3: Boron trifluoride has a trigonal planar shape. The B-F bonds in BF3 are polar, but the molecule is nonpolar due to the symmetric cancellation of bond polarities.
15. H2O: Water has a bent shape and two polar O-H bonds. The bond polarities do not cancel each other due to the bent shape, making water a polar molecule.
16. N2O: Nitrous oxide has a linear shape, and both N-O bonds are polar. However, the molecule is nonpolar due to its linear symmetry.
17. AsH3: Arsine has a pyramidal shape, and the As-H bonds are polar. The molecule is polar due to the opposing polarities of the bonds.
Based on the analysis above, the nonpolar molecules are H2S, C2H2, SiF4, CS2, CF4, and N2O.