7.1.3 - Laboratory Activity : Properties of an acid

Laboratory Activity 7.1.3: Properties of an acid

Aim: To study the chemical properties of acid

Material: » Magnesium ribbon » Copper (II) oxide powder » Hydrochloric acids » Lime water » Copper(II) carbonate

Apparatus: » Test tube » Holder » Delivery tube » Wooden splint » Spatula » Bunsen burner

Procedure:

	►	The animation below shows the arrangement and results of the experiment.
	►	(A) Reaction with magnesium 1. 10cm3 dilute hydrochloric acid is poured into a test tube. 2. A piece of magnesium ribbon is dropped into the test tube. 3. The test tube is heated gently. 4. The gas evolves is tested with a lighted wooden splinter.
	►	(B) Reaction with copper (II) carbonate 1. Several pieces of copper carbonate are placed into a test tube. 2. 10cm3 dilute hydrochloric acid is poured into the test tube. 3. The test tube is heated gently. 4. The gas evolves is tested with lime water.
	►	(C) Reaction with copper(II) oxide 1. 10cm3 dilute hydrochloric acid is poured into a test tube. 2. A spatula of copper(II) carbonate is added into the test tube. 3. The test tube is heated gently. 4. All observations are recorded.

Results:

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Test Observation (A) Reaction with magnesium Effervescence occurs. Gas evolves produces a 'pop' sound with a lighted wooden splinter. (B) Reaction with copper(II) carbonate Effervescence occurs. Gas evolves turns the lime water chalky. (C) Reaction with copper oxide(II) Black copper(II) oxide powder dissolves to form a blue solution.

Discussion:

	►	An active metal [magnesium] reacts with dilute acid[hydrochloric acid] to produces hydrogen gas and salt. ○ HCl(aq) + Mg(s) → MgCl2(aq) + H2(g)
	►	A dilute acid produces carbon dioxide, water and a salt from all carbonate. ○ HCl(aq) + CuCO3(s) → CuCl2(aq) + H2O(l) + CO2(g)
	►	A dilute acid react with base or alkali to form a salt and water only . ○ 2HCl(aq) + CuO(s) → CuCl2(aq) + H2O(l)

Conclusion:

	►	Acids react with active metals like magnesium to produce a salt and hydrogen gas.
	►	Acids react with carbonate to produce a salt, water and carbon dioxide.
	►	All acids react with a base or alkali to form a salt and water only.

↶ 7.1 Acids and Bases

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