Question

give the number of valance and core electrons for each. valence electrons are from the group number. core electrons are not valence electrons. it is valence electrons that are gained or lost in a chemical reaction.
f has 1 valence electrons and 2 core electrons
f⁻¹ has 3 valence electrons and 4 core electrons
cl has 5 valence electrons and 6 core electrons
cl⁻¹ has 7 valence electrons and 8 core electrons
a. 0 b. 1 c. 2 d. 3 e. 4 f. 5 g. 6 h. 7 i. 8
j. 9 k. 10 l. 11 m. 12 n. 13 o. 14 p. 15 q. 16 r. 17
s. 18 t. 19 u. 20

Explanation:

Step1: Determine F valence electrons

Fluorine (F) is in group 17. So it has 7 valence electrons.

Step2: Determine F core electrons

F has atomic number 9. Core electrons = 9 - 7 = 2.

Step3: Determine F⁻ valence electrons

F⁻ has gained 1 electron. So valence electrons = 7+ 1=8.

Step4: Determine F⁻ core electrons

Core electrons remain the same as in F, which is 2.

Step5: Determine Cl valence electrons

Chlorine (Cl) is in group 17. So it has 7 valence electrons.

Step6: Determine Cl core electrons

Cl has atomic number 17. Core electrons = 17 - 7 = 10.

Step7: Determine Cl⁻ valence electrons

Cl⁻ has gained 1 electron. So valence electrons = 7 + 1=8.

Step8: Determine Cl⁻ core electrons

Core electrons remain the same as in Cl, which is 10.

Answer:

1. H. 7
2. C. 2
3. I. 8
4. C. 2
5. H. 7
6. K. 10
7. I. 8
8. K. 10