Question

Write the chemical symbols for three different atoms or atomic cations with 29 electrons.

Answer 1

Answer: $Cu,Zn^{+}and Ga^{2+}$ are atom and cations with 29 number of electrons.

Explanation:

1) An element with atomic number 29 is copper.Which means that there are 29 electrons and 29 protons present in an atom of a copper. And it is represented s Cu as it is a neutral atom no net charge on the atom will written.

2) Zinc has atomic number of 30 . which means that there are 31 electrons and 31 protons present in an atom of a nickel. If zinc atom looses 1 electron it total number of electrons changes to 29 and that is represent as$Zn^{+}$.

3) Gallium has  has atomic number of 31 . which means that there are 30 electrons and 30 protons present in an atom of a nickel. If zinc atom looses 2 electrons it total number of electrons changes to 29 and that is represent as$Ga^{2+}$.

Answer 2

The element being referred in here with 29 as the atomic number is copper (Cu). Copper is a soft, malleable, and is very ductile. It also has a very high thermal conductivity making it a top choice when it comes to wiring. 

In chemistry, there exist an Octet rule which states that for an atomic to achieve stability, it allows itself to gain or loss electron so that the last shell will contain only 8 electrons.

The number divisible by 8 that is nearest to 29 is 32. Therefore, the atom should have the following cations,
          Cu⁺, known as cuprous
          Cu²⁺, known as cupric 
and    Cu³+, known as copper (III)