posted by lyne .
Ca(s) + Br2(l) --> CaBr2 is synthesis
my teacher also said that the cause of the reaction is stable electron configuration
is that the same thing as the electrolytes one
No, this is an oxidation/reduction reaction. The Ca(s) is oxidized because it loses electrons. The Br2(l) is reduced because it gains electrons. (The Ca goes from an oxidation state of zero to an oxidation state of +2 and the Br goes from an oxidation state of zero to an oxidation state of -1 for each Br atom.) And the Ca does reach a stable electron configuration by losing it outside shell of two electrons to form Ca^+2 AND the Br atoms each gain one electron to reach a stable electron configuration to form Br^-. CaBr2 is an ionic compound. The reaction is analogous to the reaction between Na metal and Cl2 gas.