Chemistry Periodic table help?

Question

Which of these elements would have to gain electrons to become stable?

Ga
Ge
As
Ta
Si
Sn
Te
Kr
Mo

Which of these would have to lose electrons to become stable?

Answer 1

Ga - 3th group element - lose 3 elections to stabilize
Ge - 4th group element - gains/lose 4 electrons to stabilize
As - 5th group element - gains 3 electrons to stabilize
Ta - Transition element - loses 2 electrons to stabilize
Si - 4th group element - gains/lose 4 electrons to stabilze
Sn - 4th group element - loses 4 electrons to stabilize (Tin - metal, they are usually positive charged)
Te - 6th group element - gains 2 electrons to stabilize
Kr - 8th group element - stabilized - with 8 electrons at the most outer shell
Mo - transition element - loses 2 electrons to stabilize

Answer 2

I am not going to do your homework for you but consider this:

Look at the periodic table. The elements on the left need to shed electrons to become stable. The elements on the right need to gain electrons to become stable. The larger the atom (bottom of the table is larger than top of the table) the less needy the element is to gain or lose electrons. So from that info you should be able to figure out the order of your list.

Just to start Kr (Krypton) is a noble gas and it is already stable.

Answer 3

Since Kr is a noble gas, it's already stable and doesn't need to lose or gain electrons. The metals would need to lose enough electrons until their valence shell has 8 electrons, and the nonmetals would need to gain enough electrons until their valence shell has 8 electrons. Now if the metals are transition metals, depending on what other atoms / ions are around will determine how many electrons they need since because of their structure, they could have more than one way to satisfy the octet rule.

Answer 4

Only Te has 6 electrons on its external shell and could gain 2 electrons to be stable