Predict how many electrons will most likely be gained or lost by each of the following elements.
(a) Se
Will it gain or lose electrons?
gain
lose
number of electrons
(b) Cl
Will it gain or lose electrons?
gain
lose
number of electrons
(c) Al
Will it gain or lose electrons?
gain
lose
number of electrons
(d) Ba
Will it gain or lose electrons?
gain
lose
number of electrons
How do you know if it will lose or gain electrons.
2 answers
You know the tendency from its position on the periodic table. Metals lose electrons.
Look at the periodic table.
If the element is in groups I, II, or III (or groups 1, 2, and 13 depending upon the system your prof is using), the element has an extra 1, 2, or 3 electrons in the outer shell and will lose 1, 2, or 3 electrons. If the element is in group V, VI, or VIII (or groups 15, 16, 17), it has 5, 6, or 7 electrons in the outer shell and will GAIN 3 electrons (to make 8 from 5), gain 2 electrons (to make 8 from 6) or gain 1 electron (to make 8 from 7).
Elements in group 0 (or 18) already have 8 electrons in their outer shell and they neither gain nor lose electrons. Group IV (group 14) elements have 4 electrons in their outer shell and usually neither gain nor lose; rather they almost always SHARE electrons to complete their outer shells.
If the element is in groups I, II, or III (or groups 1, 2, and 13 depending upon the system your prof is using), the element has an extra 1, 2, or 3 electrons in the outer shell and will lose 1, 2, or 3 electrons. If the element is in group V, VI, or VIII (or groups 15, 16, 17), it has 5, 6, or 7 electrons in the outer shell and will GAIN 3 electrons (to make 8 from 5), gain 2 electrons (to make 8 from 6) or gain 1 electron (to make 8 from 7).
Elements in group 0 (or 18) already have 8 electrons in their outer shell and they neither gain nor lose electrons. Group IV (group 14) elements have 4 electrons in their outer shell and usually neither gain nor lose; rather they almost always SHARE electrons to complete their outer shells.