Respuesta :

Answer:

F= -1 (group 7A)

Ca= +2 (group 2)

Explanation:

oxidation #= # electrons atom gains/loses to form chemical bond

>assigned to atoms in oxidation-reduction rxn to indicate ability to donate/ gain e-

> positive oxidation #= loss of e-, negative= gain of e-

rules:

all group 2 elements (ca) have an oxidation state of 2+

group 7A (F)= -1 charge (needs to gain 1 e- to complete octet)