Answer:
The correct statement about the two Lewis structures is option C: Both HCN and HNC have +1 and -1 formal charges, but in HCN the negative formal charge is on the more electronegative atom.
In Lewis structures, formal charges are used to determine the distribution of charges in a molecule. Formal charge is calculated by assigning electrons in a covalent bond to the more electronegative atom and determining the difference between the valence electrons of an atom and its lone pair electrons or shared electrons.
In the Lewis structures of HCN and HNC, both have a total of 10 valence electrons. Let's analyze each structure to determine the correct statement:
- For HCN: Hydrogen (H) has a formal charge of +1 since it has one valence electron and zero lone pairs. Carbon (C) has a formal charge of 0 since it has four valence electrons and no lone pairs. Nitrogen (N) has a formal charge of -1 since it has five valence electrons and one lone pair.
- For HNC: Hydrogen (H) has a formal charge of 0 since it has one valence electron and no lone pairs. Nitrogen (N) has a formal charge of +1 since it has five valence electrons and zero lone pairs. Carbon (C) has a formal charge of -1 since it has four valence electrons and one lone pair.
Comparing the formal charges in HCN and HNC, we can see that both molecules have +1 and -1 formal charges. However, in HCN, the negative formal charge is on the more electronegative atom, nitrogen (N). Hence, option C is the correct statement.
Step-by-step explanation: