which of the following tetrahedral molecules is polar? please explain
CH4
CF4
CH3F
thanks
CH4 is not.
CF4 is not
CH3F is.
All three molecules are tetrahedral shapes. The C-H bonds are slightly polar BUT the tetrahedral shape is symmetrical and the individual bond polarities cancel so the overall polarity is zero for the molecule. Same argument for CF4. However, for CH3F that C-F bond doesn't cancel out the resultant CH3 bonds so the molecule is polar. Said another way the CH3F molecule is not symmetrical. It's the same kind of thing, but easier to see, that the O=C=O molecule has polar bonds but the molecule is not polar because the two polar bonds cancel each other. But O=C=S would be polar because the O=C doesn't quite cancel the C=S bond.
Well, let me just put on my "chemistry clown" nose and give you a comedic breakdown of these tetrahedral molecules!
First up, we have CH4, also known as methane. Now, imagine a little carbon atom hanging out in the center, surrounded by four cheeky hydrogen atoms. Unfortunately, when it comes to polarity, this molecule is as balanced as a circus acrobat on a tightrope. CH4 is nonpolar because the electronegativity difference between carbon and hydrogen is so small that they share electrons equally. No polarity in this clown act!
Next, we come to CF4, or carbon tetrafluoride. Picture a sneaky carbon atom trying to hide in the middle while four mischievous fluorine atoms dance around it. Now, this molecule may seem like a potential candidate for polarity, given the electronegativity difference between carbon and fluorine. However, these fluorine clowns are evenly spaced around the carbon atom, resulting in a symmetrical arrangement that cancels out any dipole moment. Just like a magic trick, CF4 pulls a disappearing act on polarity!
Lastly, we have CH3F, also known as methyl fluoride. We've got our trusty carbon atom in the center, along with three hydrogen atoms and one playful fluorine atom. In this clown circus, the carbon-hydrogen bonds are nonpolar due to the small electronegativity difference. However, the carbon-fluorine bond is polar because fluorine is more electronegative than carbon, giving it a partial negative charge. As a result, the molecule as a whole is polar. CH3F takes home the polarity prize with its quirky mix of polar and nonpolar bonds!
So, in conclusion, out of the three tetrahedral molecules, only CH3F is polar. The other two, CH4 and CF4, blend in with the nonpolar crowd. Remember, chemistry can be a circus of elements, so always embrace the entertaining side of science!
To determine if a molecule is polar or not, we shall consider the molecular geometry and the polarity of its individual bonds.
1. CH4 (Methane):
- Methane consists of four hydrogen atoms bonded to a central carbon atom.
- The molecule has a tetrahedral shape, with the carbon atom in the center and the four hydrogen atoms occupying the corners of the tetrahedron.
- Since the carbon-hydrogen bonds are nonpolar, and the molecule is symmetrical (the four hydrogens are evenly distributed around the carbon atom), CH4 is a nonpolar molecule.
2. CF4 (Carbon tetrafluoride):
- Carbon tetrafluoride consists of a central carbon atom bonded to four fluorine atoms.
- The molecule also has a tetrahedral shape, similar to methane.
- However, unlike CH4, the carbon-fluorine bonds are polar, with the fluorine atoms being more electronegative than carbon.
- Despite this, the molecule is nonpolar because the individual bond polarities cancel each other out due to the symmetrical arrangement of the fluorine atoms around the carbon atom.
3. CH3F (Methyl fluoride):
- Methyl fluoride consists of a central carbon atom bonded to three hydrogen atoms and one fluorine atom.
- Like CH4 and CF4, CH3F also has a tetrahedral arrangement of atoms.
- However, in CH3F, the carbon-fluorine bond is polar because fluorine is more electronegative than carbon.
- Due to the asymmetrical arrangement of the atoms, the molecule is polar.
In conclusion, out of the three tetrahedral molecules, only CH3F (Methyl fluoride) is polar due to the presence of a polar carbon-fluorine bond. Both CH4 (Methane) and CF4 (Carbon tetrafluoride) are nonpolar because their bond polarities cancel each other out.
To determine whether a molecule is polar or nonpolar, we need to consider the molecular geometry and the polarity of the individual bonds present in the molecule.
In this case, we are comparing the tetrahedral molecules CH4 (methane), CF4 (carbon tetrafluoride), and CH3F (fluoromethane).
Let's start by looking at CH4 (methane). Methane has four hydrogen atoms bonded to a central carbon atom, resulting in a tetrahedral shape. Since carbon and hydrogen have similar electronegativity values, the carbon-hydrogen bonds are nonpolar. Additionally, the molecule as a whole is symmetrical, meaning that the dipole moments of the individual carbon-hydrogen bonds cancel each other out. Therefore, CH4 (methane) is a nonpolar molecule.
Next, let's consider CF4 (carbon tetrafluoride). Carbon tetrafluoride also has a tetrahedral shape, with four fluorine atoms bonded to a central carbon atom. Fluorine is highly electronegative, meaning it attracts electrons strongly. As a result, the carbon-fluorine bonds in CF4 are highly polar. However, the molecule remains nonpolar because the dipole moments of the bond are symmetrical and cancel each other out.
Finally, let's examine CH3F (fluoromethane). Like methane, CH3F has a tetrahedral shape, but the difference is that one hydrogen atom is replaced by a fluorine atom. Fluorine is much more electronegative than carbon and hydrogen, resulting in a polar carbon-fluorine bond. Additionally, unlike methane and carbon tetrafluoride, the molecule is asymmetrical due to the presence of the fluorine atom. This asymmetry leads to an overall molecular dipole moment, making CH3F a polar molecule.
In conclusion, among the given options, CH3F (fluoromethane) is the only polar molecule.