Dados los siguientes iones: O2- ; F-; Ca2+; K+. Indica el número de protones y de electrones de cada uno.
(números atómicos: O = 8 ; F = 9 ; Ca = 20 ; K = 19)

Calculate the change in entropy if br2(l) is converted to br2(g). s° for br2(l) = 152.2 j/(mol•k) s° for br2(g) = 245.5 j/(mol•k) s° for br(g) = 175.0 j/(mol•k)

Y=‐1x + 7 if y has a value of ‐24 what is the value of x?

Plz choose one of the compounds from the table and explain how you know the numbers of atoms in your formula. is it possible for two different compounds to be made from the exact same two elements? why or why not? with a limited number of elements (less than 120 are known), does this mean we also have a small number of compounds or do we have a large number of compounds in this world?