Problem 49 - Chemistry and Chemical Reactivity

Question

Siderite is a mineral consisting largely of iron(II) carbonate. Write an overall, balanced equation for its reaction with nitric acid, and name the products.

Step-by-Step Solution

Answer

The reaction of siderite with nitric acid produces iron(II) nitrate, carbon dioxide, and water: \(FeCO_3 + 2HNO_3 \rightarrow Fe(NO_3)_2 + CO_2 + H_2O\).

Step 1: Identify Reactants

The problem describes a reaction between siderite, which is primarily composed of iron(II) carbonate \((FeCO_3)\), and nitric acid \((HNO_3)\). These are the substances that will react according to the problem.

Step 2: Write Equation for Products Formation

When \((FeCO_3)\) reacts with \((HNO_3)\), it typically forms iron(II) nitrate \((Fe(NO_3)_2)\), carbon dioxide \((CO_2)\), and water \((H_2O)\). The general reaction can be written without balancing as: \[FeCO_3 + HNO_3 \rightarrow Fe(NO_3)_2 + CO_2 + H_2O\]

Step 3: Balance the Chemical Equation

Balance the number of each type of atom on both sides of the equation. For this reaction, you need two moles of \(HNO_3\) for each mole of \(FeCO_3\) to balance the numbers of hydrogen and nitrate ions. The balanced equation is: \[FeCO_3 + 2HNO_3 \rightarrow Fe(NO_3)_2 + CO_2 + H_2O\]

Step 4: Identify and Name Products

The products of the reaction are iron(II) nitrate \(Fe(NO_3)_2\), carbon dioxide \(CO_2\), and water \(H_2O\). These names are derived from their chemical formulas.

Key Concepts

Mineral Chemistry

Mineral chemistry is the study of the chemical compositions and structures of minerals. Minerals are naturally occurring, solid compounds with a definite chemical structure. Understanding mineral chemistry helps us to know how minerals interact with each other and with various chemicals. In the context of the siderite and nitric acid reaction, we see mineral chemistry at play.

Siderite is a mineral composed primarily of iron(II) carbonate \(FeCO_3\). This means that in this mineral, iron atoms are bonded with carbonate ions \((CO_3^{2-})\). When an acid like nitric acid \((HNO_3)\) is introduced to siderite, a reaction ensues that breaks those original bonds and forms new compounds. This is a fundamental concept in mineral chemistry which allows us to predict the formation of new substances when minerals react with acids.

Iron Compounds

Iron compounds are substances that contain iron atoms bonded with other elements. Iron is a versatile element and forms a wide range of compounds.

In the reaction of siderite \((FeCO_3)\) with nitric acid, iron transitions from the carbonate compound to form iron(II) nitrate \((Fe(NO_3)_2)\). This transformation illustrates a key aspect of chemistry where iron's oxidation state does not change, but its chemical environment does. Iron(II), in particular, refers to iron in the +2 oxidation state. These compounds are generally more reactive and soluble in comparison to iron(III) compounds, making them interesting subjects in both academic studies and industrial applications. Such reactions demonstrate how iron compounds can contribute to various chemical processes by forming different products.

Nitric Acid Reactions

Nitric acid \((HNO_3)\) is a strong acid known for its ability to react with metals and carbonate minerals. It is often involved in reactions that lead to the formation of nitrates, a group of compounds that contain nitrogen and oxygen atoms in specific configurations.

In the case of the siderite reaction, nitric acid reacts with the mineral to produce iron(II) nitrate, carbon dioxide, and water. The process typically involves the donation of hydrogen ions \((H^+)\) which interact with the carbonate molecules, leading to the formation of carbon dioxide \((CO_2)\). This means that nitric acid acts both as a proton donor and an oxidizer, facilitating the breakdown of \(FeCO_3\) and the rearrangement into the stable products \(Fe(NO_3)_2\), \(CO_2\), and \(H_2O\). It's important to balance such reactions to ensure that the conservation of mass is followed, showing that all atoms present in the reactants are accounted for in the products.