0.2 mol of a simple substance in whose atoms there are 9 protons each entered into a chemical reaction

0.2 mol of a simple substance in whose atoms there are 9 protons each entered into a chemical reaction with another simple substance in the atoms of this simple substance contained twenty protomes how much of the compound was formed as a result of the reaction?

Given:
n (simple substance E1) = 0.2 mol
E1 – 9 protons
E2 – 20 protons

To find:
n (product) -?

Solution:
1) Using the periodic system of D.I.Mendeleev, determine E1:
9 protons contains the chemical element fluorine – F;
2) Using the periodic system of D.I.Mendeleev, determine E2:
20 protons contains the chemical element calcium – Ca;
3) Write the equation of a chemical reaction:
F2 + Ca => CaF2;
4) Determine the amount of CaF2 substance:
n (CaF2) = n (F2) = 0.2 mol.

Answer: The amount of CaF2 substance is 0.2 mol.