The following bonds, C-H and C-C, are___
A nonpolar
B polar
C hydrogen
D ionic
The correct answer and explanation is :
The correct answer is:
A) Nonpolar
Explanation:
1. Understanding Bond Polarity:
Bond polarity is determined by the difference in electronegativity between two bonded atoms. Electronegativity is a measure of an atom’s ability to attract electrons in a bond. When the difference is:
- Greater than 1.7: The bond is ionic (one atom completely transfers electrons to another).
- Between 0.5 and 1.7: The bond is polar covalent (unequal sharing of electrons).
- Less than 0.5: The bond is nonpolar covalent (equal or nearly equal sharing of electrons).
2. Electronegativity of Carbon and Hydrogen:
- Carbon (C): 2.55
- Hydrogen (H): 2.20
The electronegativity difference between carbon and hydrogen is 2.55 – 2.20 = 0.35, which is less than 0.5, indicating a nonpolar covalent bond.
3. Electronegativity of Carbon and Carbon:
A bond between two identical atoms (C-C) has an electronegativity difference of zero, making it a completely nonpolar covalent bond.
4. Why Not Other Options?
- B) Polar: Incorrect, because the electronegativity differences are too small.
- C) Hydrogen Bond: Incorrect, as hydrogen bonding occurs between molecules, not within covalent bonds.
- D) Ionic: Incorrect, since there is no electron transfer, only sharing.
Conclusion:
Both C-H and C-C bonds are nonpolar due to their small or zero electronegativity differences, leading to nearly equal sharing of electrons.