Final answer:
The concentration of the solution is 0.021 moles per liter.
Step-by-step explanation:
To find the concentration of the solution, we divide the number of moles of lithium fluoride by the volume of the solution:
Concentration = Moles / Volume
Given that there are 4.2 moles of lithium fluoride and 200 liters of solution, we can calculate the concentration:
Concentration = 4.2 moles / 200 liters = 0.021 moles per liter
Therefore, the concentration of the solution is 0.021 moles per liter.