Answer: Salt and Water
Explanation:
An Arrhenius acid (HCl) can best be defined as any substance that when added to water increases the concentration of H+ ions.
While an Arrhenius base (KOH) is any substance that when added to water increases the concentration of OH- ions.
When an Arrhenius acid such as HCl reacts with an Arrhenius base such as KOH, the end products will be salt and water, in a process called Neutralization Reaction.
HCl (aq) + KOH (aq) -------> KCl (aq) + H2O (l)
If you have 58.93g of Co it means that you only have 1 mol (use a periodic table to find the answer, if you had more find it by proportion, it's easier).
There's 6.022 x 10^23 atoms per mol so you have 6.022 x 10^23 atoms of Co.
(once again if you had more mol, you could find the answer by proportions).