C. MgCl2
This structure forms a ionic bond, which are generally stronger than covalent bonds. All of the other choices are covalent.
Answer: a. Hydrofluoric acid
d.sulfuric acid
e. Dihydrogen phospataion
b.hydrobromic acid
c. Nitric acid
Explanation:
The reaction will be: FeBr2 + K --> KBr + Fe
Balancing gives: FeBr2 + 2K --> 2KBr + Fe
The molar mass of FeBr2 is 55.85 + 2*79.9 = 215.65 g/mol.
We divide 40 g / 215.65 g/mol = 0.185 mol FeBr2
Based on stoichiometry:
(0.185 mol FeBr2)(2 mol KBr/1 mol FeBr2) = 0.370 mol KBr