Question

When dissolved in water, which of the following would conduct electricity the best?

Answer

SrCl2

C2H6

H2O

Cl2

Answer 1

H2O "dissolved" in water is still water. >_>
C2H6 is a molecular compound that does not dissociate into ions, so it cannot conduct electricity. Same thing with Cl2.
SrCl2 is an ionic compound. When part of an aqueous solution (water), the compound breaks into Sr+ and Cl- ions. This is how we can conduct electricity.

Answer 2

think of electrolytes