Question

Write a chemical equation for solid cadmium hydrogen carbonate decomposing to yield solid cadmium carbonate, water, and carbon dioxide gas.

Short answer

The balanced equation is \( \text{Cd(HCO}_3\text{)}_2 (s) \rightarrow \text{CdCO}_3 (s) + \text{H}_2\text{O} (l) + \text{CO}_2 (g) \).

Step-by-step solution

Identify the Formula of Reactants

The reactant given is solid cadmium hydrogen carbonate, which has the chemical formula \( \text{Cd(HCO}_3\text{)}_2 \).

Determine the Products

When cadmium hydrogen carbonate decomposes, it produces cadmium carbonate (CdCO3), water (H2O), and carbon dioxide (CO2).

Write the Chemical Equation

Using the chemical symbols from Steps 1 and 2, we set up the balanced chemical equation: \[ \text{Cd(HCO}_3\text{)}_2 (s) \rightarrow \text{CdCO}_3 (s) + \text{H}_2\text{O} (l) + \text{CO}_2 (g) \]

Verify Balancing

Check that the equation is balanced. Each element has the same number on both sides: Cd (1), C (3 total), H (2), and O (6 total). The equation is balanced.

Key concepts

Decomposition Reaction

A **decomposition reaction** is a type of chemical reaction where one compound breaks down into two or more simpler substances. It is essentially the reverse of a synthesis reaction, where simpler substances combine to form a more complex compound. Decomposition reactions are characterized by a single reactant, which splits into multiple products.

These reactions require energy input, which can come from various sources such as heat, light, or electricity, to overcome the bonds holding the compound together. For example, in the decomposition of **cadmium hydrogen carbonate**, energy causes it to break apart into cadmium carbonate, water, and carbon dioxide.

Decomposition reactions play a crucial role in various scientific processes and everyday applications. They are used in processes like:

• Food digestion: Breaking down complex molecules into simpler nutrients.
• Recycling: Chemical decomposition of waste to reclaim raw materials.
• Thermal decomposition: Involves heating to decompose compounds.

Chemical Balancing

**Chemical balancing** is the process of ensuring that a chemical equation has equal numbers of each type of atom on both sides of the equation. Balancing chemical equations is important because it reflects the conservation of mass, where no atoms are lost or gained during a reaction.

In a balanced equation for the decomposition of cadmium hydrogen carbonate, it is necessary to check that the numbers of each type of atom are the same on both the reactant and product sides:

• Cadmium (Cd) atoms: 1 on both sides.
• Carbon (C) atoms: 3 in total - 1 in cadmium carbonate and 2 in carbon dioxide.
• Hydrogen (H) atoms: 2, all in water.
• Oxygen (O) atoms: 6 in total - combined in cadmium carbonate, water, and carbon dioxide.

Each element must be counted carefully to ensure they match, maintaining the equality required for a balanced chemical equation. If an equation isn't balanced initially, coefficients can be adjusted to achieve balance without altering the chemical formulas.

Inorganic Chemistry

**Inorganic chemistry** is the branch of chemistry concerned with compounds that are not primarily made of carbon. It encompasses the study of metals, minerals, and organometallic compounds. **Cadmium hydrogen carbonate**, and its decomposition, is an example of an inorganic reaction involving cadmium, a transition metal.

Inorganic reactions, like the decomposition of cadmium hydrogen carbonate, often involve ionic compounds and metals, and they typically follow the principles of reaction types such as synthesis, decomposition, single and double replacement, and redox reactions.

Understanding inorganic chemistry is essential for various industrial applications, including:

• Catalysts: For speeding up chemical reactions without consumption.
• Coatings and pigments: Used in paints and ceramics.
• Fertilizers: Incorporating essential nutrients into soil.

Inorganic chemistry is vast, covering all elements of the periodic table except for organic carbon compounds, making it foundational to a wide array of scientific and industrial disciplines.