The correct statement is: "This solution would be able to produce carbon dioxide when reacted with sodium carbonate."
Calcium hydroxide, Ca(OH)2, is a base that can react with acids to form salts and water. When it reacts with carbon dioxide (CO2), it forms calcium carbonate (CaCO3), water, and releases carbon dioxide gas according to the following equation:
Ca(OH)2 (aq) + CO2 (g) → CaCO3 (s) + H2O (l) + CO2 (g)
Sodium carbonate, Na2CO3, is a salt that contains a carbonate ion (CO3 2-) which can react with Ca(OH)2 to produce calcium carbonate and sodium hydroxide according to the following equation:
Ca(OH)2 (aq) + Na2CO3 (aq) → CaCO3 (s) + 2 NaOH (aq)
Therefore, when Ca(OH)2 solution reacts with sodium carbonate solution, it would produce calcium carbonate and release carbon dioxide gas.
The other statements are not true because:
- The pH of a 1.6 × 10-3 M solution of Ca(OH)2 would be around 12.3, not 11.51. This is because Ca(OH)2 is a strong base and completely dissociates in water to produce hydroxide ions (OH-) which would raise the pH of the solution.
- Ca(OH)2 is not a strong enough base to dissolve most metals, so the statement "This solution could dissolve metal" is not true.
- Litmus is an indicator that changes color in acidic or basic solutions. Since Ca(OH)2 is a base, it would turn litmus paper blue, not red.