Reactivity Series：練習題

A strip of copper is placed in an aqueous solution of silver nitrate, \(AgNO_3(aq)\). Which observation would be expected based on the reactivity series?

When a mixture of magnesium powder and iron(III) oxide is heated strongly, a vigorous reaction occurs. However, when a mixture of silver powder and iron(III) oxide is heated under the same conditions, no reaction is observed.

Which statement correctly explains these observations based on the reactivity series?

A student investigates the thermal stability of four different metal carbonates: \(WCO_3\), \(XCO_3\), \(YCO_3\), and \(ZCO_3\). The time taken for 50 \(cm^3\) of limewater to turn milky when the carbonates are heated with the same intensity is recorded below:

\(WCO_3\): 25 seconds
\(XCO_3\): 120 seconds
\(YCO_3\): No change after 10 minutes
\(ZCO_3\): 60 seconds

What is the increasing order of reactivity of the metals \(W, X, Y,\) and \(Z\)?

Four metals \(W\), \(X\), \(Y\) and \(Z\) were tested to determine their relative reactivity. The following results were obtained:
1. \(W\) can reduce the oxide of \(X\) when heated.
2. Only \(Y\) and \(Z\) react with steam.
3. \(Y\) reacts more vigorously with cold water than \(Z\).

What is the decreasing order of reactivity for these metals?

In the extraction of metals from their ores, some metals can be obtained by heating their oxides with carbon, while others require electrolysis.

Which of the following pairs correctly identifies a metal that can be extracted using carbon and a metal that must be extracted via electrolysis?

A piece of magnesium ribbon is added to a test tube containing aqueous copper(II) sulfate. State the observations made during the reaction and identify the type of reaction that has occurred.

When a mixture of magnesium powder and iron(III) oxide is heated strongly, a vigorous reaction occurs. Write a balanced chemical equation for this reaction, including state symbols, and identify which substance is the reducing agent.

An unknown metal carbonate, \(MCO_3\), is heated. It decomposes to form a black metal oxide and a gas that turns limewater milky. When the resulting metal oxide is heated with carbon, the metal \(M\) is obtained. Suggest the identity of metal \(M\) and explain its position in the reactivity series relative to carbon.

The reactivity of four metals, \(A\), \(B\), \(C\), and \(D\), was investigated. It was found that:
1. Only metal \(A\) and \(B\) react with cold water.
2. Metal \(B\) reacts more vigorously with water than metal \(A\).
3. Metal \(C\) can reduce the oxide of metal \(D\) when heated.
4. Metal \(D\) does not react with steam, but metal \(C\) does.

(a) Arrange the metals in decreasing order of reactivity.
(b) Predict which of these metals is most likely to be found as a native element in the Earth's crust. Explain your answer.
(c) Write a balanced chemical equation for the reaction of metal \(A\) with water, assuming \(A\) is sodium.

Iron is a widely used metal but is susceptible to corrosion (rusting).

(a) State the two essential conditions required for iron to rust.
(b) Magnesium blocks are often attached to the steel hulls of ships to prevent rusting. Identify this method of protection and explain how it works in terms of the reactivity series.
(c) Explain why galvanising provides better protection than painting if the surface of the object is scratched.
(d) Write the ionic half-equation for the oxidation of iron atoms during the rusting process: \(Fe \rightarrow Fe^{2+} + 2e^{-}\). Suggest what happens to the electrons released.