Answer:
The dissociation equations for NaBr gives Na+ and Br-
The dissociation equations for ZnCl2 gives Zn2+ and 2 Cl-
Explanation:
The following pictures shows that the dissociation of one particle of NaBr produces one particle of Na+ (sodium cation) and one particle of Br- (bromine anion).
The dissociation of one particle of ZnCl2 produces one particle of Zn+2 (Zinc cation) and two particles of Cl- (chlorine anion).
Answer:
5 electrons
Explanation:
Valence electrons are electrons located in the outermost energy shell, so you want to count the number of electrons in the last energy shell.
You can divide the configuration into 1s2 / 2s22p6 / 3s23p3 to see the energy shells in this atom. There are 3 shells occupied by the atom's electrons, so you need to count the electrons in the third shell as those are its valence electrons.
2 + 3 = 5 valence electrons total
Note: you don't count the 3 before the letter because that only indicates the shell level, not the number of electrons. Count only the exponents.
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