Aparticular ring contains both 18 k gold and sterling silver, with the two metals in an intricate design resembling braided ropes. the total mass of the ring is 15.0 g, and a jeweler wants to determine the masses of gold and of silver present. the clever jeweler places the ring into some hot water, heating it to a temperature of 87.6°c, and then drops the hot ring into 18.0 g of water at 21.8°c. when the ring and the water reach thermal equilibrium, the final temperature is 24.0°c. what mass of gold is present in the ring?

specific heats: 18 k gold: 0.132 j g–1 °c–1 sterling silver: 0.245 j g–1 °c–1 water: 4.184 j g–1 °c–1

i believe the answer is a.

  the   balanced   equation   for   reaction of   ca metal   with   o2 to   produce   cao   is as below

2 ca+ o2→ 2 cao2

  explanation

the reaction is   balanced     since the   number of atoms   in reactant side is   equal to   number of atoms   in   product side.   for   example   they   are 2   atom of   ca in   reactant   side   and   2   atoms of ca   in   the product side.

  the   process   is a   meet the   requirement   of   redox   reaction because :     calcium   is   oxidized   from   oxidation state 0   to 2+   while   oxygen   is reduced from   oxidation   state   0   to 2-

the volume increases