Question

When a strip of magnesium metal is heated in oxygen, it bursts into an intensely white flame and produces a finely powdered dust of magnesium oxide. Write the unbalanced chemical equation for this process.

Short answer

The unbalanced chemical equation for the reaction between magnesium (Mg) and oxygen (O₂), producing magnesium oxide (MgO) is: Mg + O₂ → MgO

Step-by-step solution

Identify the reactants and product

In this reaction, the reactants are magnesium metal (Mg) and oxygen (O₂). The product of the reaction is magnesium oxide (MgO).

Write the unbalanced chemical equation

Now that we have identified the reactants and product, we can write the unbalanced chemical equation. In this case, we have: Mg + O₂ → MgO This is the unbalanced chemical equation for the reaction between magnesium and oxygen, producing magnesium oxide.

Key concepts

Reactants and Products

Every chemical reaction involves a transformation where initial substances, known as reactants, change into new substances called products. It's much like baking a cake, where your reactants would be the individual ingredients and the product is the delicious cake you get at the end. In the specific example of heating magnesium in oxygen, magnesium (Mg) and oxygen (O₂) are the reactants, which react to form the product, magnesium oxide (MgO). When writing chemical equations, it's crucial to clearly identify and write down the reactants and products before proceeding to balance the equation.

It's helpful to think of reactants and products as the 'before' and 'after' snapshots of a chemical reaction. This visualization can assist students in understanding the role each substance plays in a reaction. By identifying what we start with (reactants) and what results from the reaction (products), we can better understand the process and effectively communicate it through a chemical equation.

Chemical Reactions

Chemical reactions are at the heart of chemistry. They describe the process in which reactants convert to products, which involves breaking and forming chemical bonds. A striking visual example is the reaction between magnesium and oxygen we're examining. When magnesium burns, it reacts fiercely with oxygen, exhibiting a bright white flame as it forms magnesium oxide. This is a synthesis reaction, where two or more simple substances combine to form a more complex compound.

Different types of chemical reactions exist, such as decomposition, single displacement, double displacement, and combustion. Understanding these different types can elevate a student's ability to predict products of reactions, which is an invaluable skill in chemistry.

Balancing Chemical Equations

After understanding reactants and products, the next step is to ensure that the chemical equation abides by the Law of Conservation of Mass, which states that mass is neither created nor destroyed in a chemical reaction. This is done through balancing the chemical equation. Basically, what goes in must come out- but in different forms. If we have one magnesium atom and two oxygen atoms as reactants, we must also have the same number of those atoms in the products.

To balance a chemical equation, one should change the coefficients (the numbers in front of the chemical formulas) until the number of atoms of each element is equal on both sides of the equation. For example, for our magnesium and oxygen reaction, the balanced equation should appear with a ‘2’ in front of both the 'Mg' and 'MgO' to show that two magnesium atoms react with one oxygen molecule (which has two oxygen atoms) to form two units of magnesium oxide. The balanced equation would be: \[2 Mg + O_2 \rightarrow 2 MgO\]

Magnesium Oxide

Magnesium oxide (MgO) is a white powdery substance, which is the product of the combination of magnesium and oxygen. This compound illustrates a basic principle of chemistry that elements can combine to form compounds with properties that are distinct from the individual elements. Magnesium by itself is a shiny, reactive metal, while oxygen is a gas that supports combustion; together as magnesium oxide, they become a stable white powder with a high melting point and several practical applications in refractory materials, as medication to relieve heartburn or as an insulating material.

The formation of magnesium oxide is a classic example used in chemistry education to represent a synthesis reaction, and the transformation of elements into compounds. It vividly demonstrates the reaction of metals with oxygen and also provides a clear illustration of how to work through identifying reactants, writing a chemical equation, and balancing it appropriately.