They're metals and they are in the same group/family
Answer:
I'm pretty sure its the one that says very little at the beginning but if I get it wrong I'm sorry
A second order reaction varies with the square of the concentration of the reactant. Therefore, halving the concentration will reduce the rate of reaction by a factor of 4.
The answer is E.
Calcium Floride (Caf2)
Hope this helped =D
