Question

Complete and balance each of the following decomposition reactions: (a) \(\mathrm{AgHCO}_{3}(s) \rightarrow\) (b) \(\mathrm{Zn}\left(\mathrm{HCO}_{3}\right)_{2}(s) \rightarrow\)

Short answer

(a) \(2\mathrm{AgHCO}_{3} \rightarrow \mathrm{Ag}_{2}\mathrm{O} + 2\mathrm{CO}_{2} + \mathrm{H}_{2}\mathrm{O}\) and (b) \(\mathrm{Zn(HCO}_{3}\mathrm{)}_{2} \rightarrow \mathrm{ZnO} + 2\mathrm{CO}_{2} + \mathrm{H}_{2}\mathrm{O}\).

Step-by-step solution

Identify the Type of Reaction

The given reactions are decomposition reactions where a single compound breaks down into two or more products. Decomposition often requires energy in the form of heat, light, or electricity.

Decompose the Compound in Reaction (a)

For reaction (a), the compound \(\mathrm{AgHCO}_{3}\) decomposes into its basic components: silver (Ag), carbon dioxide (\(\mathrm{CO}_{2}\)), and water (\(\mathrm{H}_{2}\mathrm{O}\)). Write down the equation: \[\mathrm{AgHCO}_{3}(s) \rightarrow \mathrm{Ag}_{2}\mathrm{O}(s) + \mathrm{CO}_{2}(g) + \mathrm{H}_{2}\mathrm{O}(g)\]

Balance Reaction (a)

We need to ensure that the number of each type of atom is equal on both sides. The balanced equation for reaction (a) should be: \[2\mathrm{AgHCO}_{3}(s) \rightarrow \mathrm{Ag}_{2}\mathrm{O}(s) + 2\mathrm{CO}_{2}(g) + \mathrm{H}_{2}\mathrm{O}(g)\]

Decompose the Compound in Reaction (b)

For reaction (b), the compound \(\mathrm{Zn}\left(\mathrm{HCO}_{3}\right)_{2}\) decomposes into its components: zinc oxide (\(\mathrm{ZnO}\)), carbon dioxide (\(\mathrm{CO}_{2}\)), and water (\(\mathrm{H}_{2}\mathrm{O}\)). Write the unbalanced equation: \[\mathrm{Zn}\left(\mathrm{HCO}_{3}\right)_{2}(s) \rightarrow \mathrm{ZnO}(s) + \mathrm{CO}_{2}(g) + \mathrm{H}_{2}\mathrm{O}(g)\]

Balance Reaction (b)

For reaction (b), balance the numbers of each type of atom. The balanced equation is: \[\mathrm{Zn}\left(\mathrm{HCO}_{3}\right)_{2}(s) \rightarrow \mathrm{ZnO}(s) + 2\mathrm{CO}_{2}(g) + \mathrm{H}_{2}\mathrm{O}(g)\]

Key concepts

Chemical Reactions

A chemical reaction is a process where one or more substances, known as reactants, transform into new substances, called products.
In a decomposition reaction, a single compound breaks down into two or more simpler substances. Decomposition reactions often require energy in the form of heat, light, or electricity to proceed. For example, when heating silver hydrogen carbonate, - it can decompose into silver oxide, carbon dioxide, and water.
This type of reaction is crucial in various applications such as metallurgy, where compounds are broken down to extract metals.

Balancing Equations

Balancing chemical equations is crucial to ensure the law of conservation of mass is followed. This means that the same number of each type of atom must be present in both the reactants and the products. To balance a decomposition reaction, start by writing the unbalanced equation. - Then, count the number of atoms for each element in the reactants and the products.
Adjust the coefficients, which are the numbers in front of the chemical formulas, to ensure equal numbers of each type of atom on both sides.Consider - the example of silver hydrogen carbonate decomposition: \[2\mathrm{AgHCO}_{3}(s) \rightarrow \mathrm{Ag}_{2}\mathrm{O}(s) + 2\mathrm{CO}_{2}(g) + \mathrm{H}_{2}\mathrm{O}(g)\] This balancing ensures that the number of silver, carbon, hydrogen, and oxygen atoms are the same on both sides.

Stoichiometry

Stoichiometry is the branch of chemistry that deals with the quantitative relationships between the reactants and products in a chemical reaction. Understanding stoichiometry allows for the calculation of various important values, such as:- The amount of products formed in a reaction,- The amount of reactants needed,- And even the efficiency of a chemical process.In stoichiometry, mole ratios derived from balanced chemical equations are used to convert between the amounts of different substances involved in a reaction. For instance, in the balanced decomposition reaction \[\mathrm{Zn}\left(\mathrm{HCO}_{3}\right)_{2}(s) \rightarrow \mathrm{ZnO}(s) + 2\mathrm{CO}_{2}(g) + \mathrm{H}_{2}\mathrm{O}(g)\]- You can see that for every mole of zinc bicarbonate, one mole of zinc oxide, two moles of carbon dioxide, and one mole of water are produced. This helps in understanding and predicting the outcomes of the reaction in real-world scenarios.