The answer is 2 electrons.
The electron configuration of calcium is 2:8:8:2
Calcium has two electrons in its outermost shell. These are its valence electrons and are the ones used in bonding with other elements. Valence electrons of an atom are those electrons that are in its outer energy shell or that are available for bonding.
Calcium is a metal. When metals react with non-metals, electrons are transferred from the metal atoms to the non-metal atoms forming ions. The resulting compound is known as an ionic compound.
For example, when calcium metal reacts with chlorine gas, calcium gives up its two valence electrons and Chlorine accepts them resulting in a new substance called calcium chloride in which the two elements have ended up forming ionic bonds.
Answer : The volume of stock solution needed are, 12.5 mL
Explanation :
Formula used :

where,
are the initial molarity and volume of copper (II) chloride.
are the final molarity and volume of stock solution of copper (II) chloride.
We are given:

Putting values in above equation, we get:

Hence, the volume of stock solution needed are, 12.5 mL
Answer:
The correct answer is "They can be separated by physical processes"
Explanation:
The definition of Mixtures is <em>the blending of two or more dissimilar substances</em>.
Mixtures can be divided into those that are homogeneous or heterogeneous meaning that they can be distributed evenly or can't be distributed evenly.
No of moles of MgCl2 = weight of MgCl2 / Molecular weight of MgCl2
Weight of MgCl2 =moles of MgCl2 x molecular mass of MgCl2
= 8.90 x 95=845.5 gm