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bija089 [108]
3 years ago
8

Materials chalk calcium hydroxide filter paper phenolphthalein heat source two Pyrex beakers Directions Crush some classroom cha

lk (a mixture of limestone and gypsum) finely. Mix chalk into water in a beaker. Pour the mixture through filter paper. The water appears to be "pure." Boil the water or let it evaporate away. What is left? Water also dissolves and transports minerals. In a beaker, mix calcium hydroxide and water. Filter until clear. Fill another container with water. Obtain some phenolphthalein solution and add a few drops to a glass of "pure" water. Add a few drops to the water mixed with calcium hydroxide. Give the results Explain the results.
Biology
1 answer:
Sladkaya [172]3 years ago
5 0
Phemolphthalein changes colour.(i forgot from which to which) This is because calcium hydrroxide is basic.
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