<u>Answer:</u> The symbol of the ion formed is 
<u>Explanation:</u>
An ion is formed when a neutral atom looses or gains electrons.
- When an atom looses electrons, it results in the formation of positive ion known as cation.
- When an atom gains electrons, it results in the formation of negative ion known as anion.
Electronic configuration is defined as the representation of electrons around the nucleus of an atom.
Number of electrons in an atom is determined by the atomic number of that atom.
The element present in Group 2-A and in period 4 is Calcium (Ca)
Electronic configuration of Ca atom: 
This atom will loose 2 electrons to attain stable electronic configuration similar to Argon element (noble gas)
The electronic configration of 
Hence, the symbol of the ion formed is 
0.1 M x 0.5L = 0.05 mols HCl.
Adding 25 mL 2M NaOH is
2M x 0.025 L = 0.05 mols NaOH.
What you want to do is to back off very slightly with the NaOH (you might try something like 24.95 mL which I calculate to give 0.00019 M or a pH of 3.7. Inching closer, 24.99 mL would leave H^+ of 4E-5 for pH 4.4. The problem here is two-fold.
hope it helps
I’m sorry I have to do this
Answer:
The majority of the weight in an atom is found in the nucleus.
Explanation:
The protons and neutrons that make up the nucleus of the atom may take up a tiny amount of space in comparison to the rest of the atom, but they are far more dense than the electrons that orbit the nucleus.
Basically, the answer for this would be N or NITROGEN. If we combine nitrogen with chlorine, what happens is that, it can attract more chlorine electrons towards itself. The reason is that, nitrogen is considered more electronegative compared to chlorine. So best answer for this is the first option.