Question

Write equations for the chemical reaction of alumirum, chromium, gold, iron, coppcr, magnesium, mercury, and zinc with dilute solutions of (a) bydrochloric acid and (b) sulfuric acid. If a reaction will not occur, write "no reaction" as the

Short answer

Al, Cr, Fe, Mg, Zn react with HCl and H₂SO₄, Cu and Hg do not.

Step-by-step solution

- Recall Metal Reactivity

Review the reactivity series of metals to determine which metals will react with acids. Metals such as aluminium, chromium, iron, copper, magnesium, mercury, and zinc all have different levels of reactivity with acids.

- Identify Metals That React with Hydrochloric Acid

Compare the metals with the reactivity series and determine which metals will react with hydrochloric acid (HCl). Recall that highly reactive metals will typically displace hydrogen in HCl to form a salt and hydrogen gas.

- Write Reactions with Hydrochloric Acid

Formulate the chemical equations for the reaction of each listed metal with hydrochloric acid (HCl): - Aluminium: \(2Al + 6HCl \rightarrow 2AlCl_3 + 3H_2\) - Chromium: \(2Cr + 6HCl \rightarrow 2CrCl_3 + 3H_2\) - Iron: \(Fe + 2HCl \rightarrow FeCl_2 + H_2\) - Copper: No reaction - Magnesium: \(Mg + 2HCl \rightarrow MgCl_2 + H_2\) - Mercury: No reaction - Zinc: \(Zn + 2HCl \rightarrow ZnCl_2 + H_2\)

- Identify Metals That React with Sulfuric Acid

Compare the metals with the reactivity series and determine which metals will react with sulfuric acid (H₂SO₄). Similar to hydrochloric acid, highly reactive metals will typically form a salt and hydrogen gas.

- Write Reactions with Sulfuric Acid

Formulate the chemical equations for the reaction of each listed metal with sulfuric acid (H₂SO₄): - Aluminium: \(2Al + 3H_2SO_4 \rightarrow Al_2(SO_4)_3 + 3H_2\) - Chromium: \(2Cr + 3H_2SO_4 \rightarrow Cr_2(SO_4)_3 + 3H_2\) - Iron: \(Fe + H_2SO_4 \rightarrow FeSO_4 + H_2\) - Copper: No reaction - Magnesium: \(Mg + H_2SO_4 \rightarrow MgSO_4 + H_2\) - Mercury: No reaction - Zinc: \(Zn + H_2SO_4 \rightarrow ZnSO_4 + H_2\)

Key concepts

chemical reactions

A chemical reaction happens when substances interact to form new substances. In our context, metals react with acids, forming a salt and releasing hydrogen gas. These reactions are simple yet fundamental, showing how atoms rearrange to create new compounds. Knowing the reactivity of metals helps predict the products of these reactions. When a metal reacts with acid, the general reaction can be written as:
Metal + Acid → Salt + Hydrogen
For example, when magnesium reacts with hydrochloric acid:
Mg + 2HCl → MgCl_2 + H_2
Understanding this basic concept helps in writing and predicting other similar reactions.

reactivity series

The reactivity series is a list of metals arranged by their reactivity from highest to lowest. It helps predict how metals will react with other substances like acids.

• Highly reactive metals like potassium and sodium are at the top.
• Less reactive metals like gold and platinum are at the bottom.

Metals higher in the series react more readily, often displacing hydrogen from acids to form salts. For instance, magnesium, being above zinc in the series, reacts more vigorously with acids:
Mg + 2HCl → MgCl_2 + H_2
Meanwhile, metals like copper and gold don’t react with dilute acids under normal conditions:

acid-metal reactions

Acid-metal reactions involve metals reacting with acids to produce a salt and hydrogen gas. This type of reaction helps understand chemical reactivity and application in various fields such as metallurgy and chemistry. For example:
When aluminum reacts with sulfuric acid:
2Al + 3H_2SO_4 → Al_2(SO_4)_3 + 3H_2
This equation shows that aluminum displaces hydrogen in sulfuric acid to form aluminum sulfate and hydrogen gas.
It's important to know which metals react with specific acids and predict the products formed.

writing chemical equations

Writing chemical equations is essential for understanding and communicating chemical reactions. Equations represent the reactants and products, showing how atoms rearrange during reactions. A well-balanced equation has equal numbers of each type of atom on both sides. For example, when zinc reacts with hydrochloric acid:
Zn + 2HCl → ZnCl_2 + H_2
The equation shows 1 zinc atom, 2 chlorine atoms, and 2 hydrogen atoms on both sides, maintaining the law of conservation of mass. Practicing writing balanced equations is crucial in learning chemistry. Each equation summarizes the reaction process in a way that’s easy to understand and study.