Unfortunately you did not specify the electronic configuration in the question, however since one of the answers must be a halogen, i took the liberty to attach an image with the configuration (both the simple numeric and spdf form) for all the halogen and all you have to do is match the electronic configuration you have in your question to the one in the table attached and you can then deduce the answer.
Hope this helps.
Answer:
9 moles of ions
Explanation:
Our compound is: CaCl₂(s)
We dissociate it:
CaCl₂(aq) → Ca²⁺ (aq) + 2Cl⁻(aq)
Per 1 mol of chloride, we have 1 mol of calcium cation and 2moles of chlorides, so in total we have 3 moles of ions.
Therefore in 3 moles of chloride, we would have 9 moles of ions (3 . 3)
Answer:
The standard enthalpy of formation of methanol is, -238.7 kJ/mole
Explanation:
The formation reaction of CH_3OH will be,

The intermediate balanced chemical reaction will be,
..[1]
..[2]
..[3]
Now we will reverse the reaction 3, multiply reaction 2 by 2 then adding all the equations, Using Hess's law:
We get :
..[1]
..[2]
[3]
The expression for enthalpy of formation of
will be,



The standard enthalpy of formation of methanol is, -238.7 kJ/mole