Acids, bases and salts：練習題

Which pair of oxides contains one acidic oxide and one basic oxide?

Which pair of aqueous solutions, when mixed together, will produce a precipitate of silver chloride?<\/p>

A student adds a few drops of methyl orange indicator to a test-tube containing dilute hydrochloric acid.
What is the resulting color of the solution?

State the word equation for the neutralisation reaction between dilute hydrochloric acid and sodium hydroxide solution.

Outline the practical steps required to prepare a pure, dry sample of magnesium sulfate by reacting excess magnesium metal with dilute sulfuric acid.

Compare the relative acidity and alkalinity of two solutions where Solution A turns universal indicator red and Solution B turns it purple, including their approximate pH values and the ions responsible for these colors.

Metal oxides can be classified based on their chemical behavior.

(a) Classify copper(II) oxide as either an acidic or a basic oxide and explain your choice in terms of its reaction with acids. [2]
(b) Aluminium oxide is described as an amphoteric oxide. Define the term amphoteric and state what products are formed when aluminium oxide reacts with a base. [2]

The pH scale is used to compare the relative acidity and alkalinity of aqueous solutions.

(a) Explain the difference between a strong acid and a weak acid in terms of their dissociation in water. [2]
(b) Compare the expected colors of methyl orange indicator in a solution of pH 2 and a solution of pH 10. [2]
(c) A farmer tests the soil and finds it is too acidic for certain crops. Suggest a substance the farmer could add to the soil to increase the pH and explain why this substance is suitable. [2]