A. boiling the water
B. adding excess calcium hydroxide
C. adding a calculated amount of calcium hydroxide
D. adding sodium carbonate
Correct Answer:
Option D – adding sodium carbonate
Explanation
its D because when sodium carbonate reacts with calcium hydrogentrioxocarbonate it gives sodium hydrogentrioxocarbonate and calcium trioxocarbonate. However, when it reacts with calcium sulphate, calcium carbonate and sodium tetraoxosulphate is formed