Decide which of the following bonds is least polar on the basis of electronegativities of atoms,
H---S, Si---Cl, N---Cl.
To decide which of the following bonds is least polar based on the electronegativities of the atoms (H---S, Si---Cl, N---Cl), we need to compare the electronegativity values of the atoms involved in each bond.
Electronegativity is a measure of an atom's ability to attract electrons towards itself in a chemical bond. It is usually represented by the Pauling scale, which assigns numerical values to different elements. The higher the electronegativity value, the greater the atom's ability to attract electrons.
Now, let's look at the electronegativity values of the atoms involved in each bond:
H (hydrogen) - electronegativity value of 2.20
S (sulfur) - electronegativity value of 2.58
Si (silicon) - electronegativity value of 1.90
Cl (chlorine) - electronegativity value of 3.16
N (nitrogen) - electronegativity value of 3.04
Cl (chlorine) - electronegativity value of 3.16
In general, when the electronegativity difference between two atoms is larger, the bond is more polar. The bond with the least electronegativity difference would be the least polar bond.
Comparing the electronegativity differences for each bond:
H---S: |2.20 - 2.58| = 0.38
Si---Cl: |1.90 - 3.16| = 1.26
N---Cl: |3.04 - 3.16| = 0.12
Based on the calculations, the bond with the least electronegativity difference, and therefore the least polar bond, is N---Cl.
To summarize, the bond N---Cl is the least polar bond among the given options based on the electronegativities of the atoms involved.
To determine which of the given bonds is least polar based on the electronegativities of atoms, we need to compare the electronegativity difference between the atoms in each bond.
The electronegativity trend generally increases from left to right across the periodic table and decreases down a group. The electronegativity difference between two bonded atoms determines the polarity of the bond.
Let's find the electronegativity values for each atom involved:
- Hydrogen (H): Electronegativity value = 2.20
- Sulfur (S): Electronegativity value = 2.58
- Silicon (Si): Electronegativity value = 1.90
- Chlorine (Cl): Electronegativity value = 3.16
- Nitrogen (N): Electronegativity value = 3.04
Now, let's calculate the electronegativity difference for each bond:
1. H---S: |2.20 - 2.58| = 0.38
2. Si---Cl: |1.90 - 3.16| = 1.26
3. N---Cl: |3.04 - 3.16| = 0.12
Based on the calculated electronegativity differences, we can conclude that the bond with the least polarity is the bond between nitrogen (N) and chlorine (Cl) (N---Cl) with an electronegativity difference of 0.12.
Look up the electronegativities, subtract them, and compare. The smallest difference will be the most covalent bonds (least polar).
Example:
NaCl. Na is about 0.9 and Cl is about 3.5 and the difference is about 2.6
NH3. N is about 3.0 and H is 2.1 so the different is about 0.9; thus, the N-H bond is must less polar than the NaCl bond. But we know, of course, that we call NaCl an ionic bond and NH3 bonds covalent (actually polar covalent).