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Question
A small piece of calcium metal is put into a small trough containing water. There is effervescence and white turbidity is formed.
What do you observe when a few drops of red litmus solution are added to the turbid solution.
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Solution
If dilute hydrochloric acid is added to the turbid solution, then they react and neutralize each other, forming the soluble salt calcium chloride (CaCl2) and water.
Ca(OH)2 + 2HCl → CaCl2 + 2H2O
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