How many valence electrons are in the following? (Remember to add an electron for each negative charge or to subtract one for each positive charge).
ICl2−
ONF
CH4
To determine the number of valence electrons in a molecule or ion, you need to consider the valence electrons of each individual atom and any corresponding charges.
ICl2−:
- Iodine (I) is in Group 7A, so it has 7 valence electrons.
- Chlorine (Cl) is in Group 7A as well, so each chlorine atom has 7 valence electrons.
- The negative charge on ICl2− means that you need to add one electron.
Therefore, the total number of valence electrons in ICl2− is:
7 (Iodine) + 2 x 7 (Chlorine) + 1 (extra electron) = 22 valence electrons
ONF:
- Oxygen (O) is in Group 6A, so it has 6 valence electrons.
- Nitrogen (N) is in Group 5A, so it has 5 valence electrons.
- Fluorine (F) is in Group 7A, so it has 7 valence electrons.
- There are no charges on ONF, so you do not need to add or subtract any electrons.
Therefore, the total number of valence electrons in ONF is:
6 (Oxygen) + 5 (Nitrogen) + 7 (Fluorine) = 18 valence electrons
CH4:
- Carbon (C) is in Group 4A, so it has 4 valence electrons.
- Hydrogen (H) is in Group 1A, so it has 1 valence electron.
- There are no charges on CH4, so you do not need to add or subtract any electrons.
Therefore, the total number of valence electrons in CH4 is:
4 (Carbon) + 4 x 1 (Hydrogen) = 8 valence electrons