Which of the following compounds will be most effective in melting the ice on the roads when the air temperature is below zero?
A. sodium iodide (NaI)
B. magnesium sulfate (MgSO4)
C. potassium bromide (KBr)
D. All will be equally effective.

Question

Which of the following compounds will be most effective in melting the ice on the roads when the air temperature is below zero?
 A. sodium iodide (NaI)
 B. magnesium sulfate (MgSO4)
 C. potassium bromide (KBr)
 D. All will be equally effective.

anonymous · Answer

I BELIEVE the answer would be D. Because how you tell what would be the most effective is look at how much it splits up. Because Na is in group one, it will ALWAYS split. So NaI will split into two ions. Sulfates (SO4) are always soluble unless they are paired with Ag, Hg, Pb, Ca, Ba, or Sr. Because Mg isn't any of those exceptions, MgSO4 will split into two ions. (molecules do not split.) K is also in group one so it will always split, therefore KBr will split into two ions as well. So the answer will be D - all will be equally effective.