Question

An element A reacts with water to form a solution, which turns phenolphthalein solution pink. Element A is most likely to be ______?

• A. S
• B. Mg
• C. Ag
• D. C

Answer 1

Answer:

B. Mg

• Magnesium (Mg) reacts with water to produce an alkaline solution, which turnsphenolphthalein pink.

• Metal donates electrons so, metal cause reduction of water.

• Positively charged metal ion reacts with negatively charged hydroxide ion to form magnesium hydroxide and hydrogen gas.

• Phenolphthalein indicator remains colourless in acidic solution and give pink colour in basic solution.