Question

Using the periodic table, predict the charges of the ions of the following elements:

(a) Ga,

(b) Sr,

(c) As,

(d) Br,

(e) Se.

Answer 1

Using the periodic table, predict the charges of the ions of the following elements:

 

(a) Ga

Ga is a group 3A metal (like Al); to gain the nearest noble gas configuration (Ar), Ga would lose three electrons to form the Ga+3 ion. Notice that the 3d electrons are not ionized - this closed 3d subshell is considered to belong to the \\\'core\\\' and not to the valence electrons.

 

(b) Sr

Strontium is a group 2A metal; it loses two electrons to gain the Kr configuration, and forms Sr2+ ion.

 

(c) As

As is a Group 5A nonmetal; it will tend to gain three electrons to reach an octet (a noble gas outer shell configuration.) We therefore have As3- ion.

 

(c) Br

Bromine is a Group 7A nonmetal; it will tend to gain one electron to reach an octet. We therefore have Br- ion.

 

(e) Se

Se is a Group 6A nonmetal; it will gain two electrons to achieve an octet, and will form the Se-2 ion.

Using the periodic table, predict the charges of the ions of the following elements:

 

(a) Ga

Ga is a group 3A metal (like Al); to gain the nearest noble gas configuration (Ar), Ga would lose three electrons to form the Ga+3 ion. Notice that the 3d electrons are not ionized - this closed 3d subshell is considered to belong to the \\\'core\\\' and not to the valence electrons.