General Science: Principles and Types of Chemical Reactions

Vocabulary flashcards covering fundamental chemical reaction concepts, conservation of mass, activation energy, and specific types of reactions including decomposition, acid-carbonate, acid-metal, and combustion.

Activation Energy ($E_a$)

The minimum energy required for colliding particles to overcome the energy barrier so that chemical bonds break and a reaction can occur.

Law of Conservation of Mass

The principle stating that atoms are neither created nor destroyed in a chemical reaction, but are simply rearranged, requiring chemical equations to be balanced.

Chemical Reaction Steps

The sequence of events during a reaction where reactants collide with sufficient activation energy, bonds break, atoms rearrange, and products form.

Decomposition Reaction

A chemical reaction in which a single compound breaks down into two or more simpler substances, usually requiring energy input such as heat, light, or electricity.

General Form of Decomposition Reaction

Represented as $AB \rightarrow A + B$; for example, the breakdown of hydrogen peroxide: $2H_2O_2 \rightarrow 2H_2O + O_2$.

Key Indicators of Decomposition Reactions

Observable signs of a decomposition reaction, including gas formation, heat absorption, and the breakdown of complex substances.

Everyday Examples of Decomposition Reactions

Common instances including hydrogen peroxide bubbling on a wound, baking soda decomposing when heated, and composting organic waste.

Acid–Carbonate Reaction

A chemical reaction occurring when an acid reacts with a carbonate compound to produce carbon dioxide gas ($CO_2$), water ($H_2O$), and a salt.

General Form of Acid–Carbonate Reaction

Represented as $\text{Acid} + \text{Carbonate} \rightarrow \text{Salt} + \text{Water} + CO_2$; for example, $2HCl + Na_2CO_3 \rightarrow 2NaCl + H_2O + CO_2$.

Key Indicators of Acid–Carbonate Reactions

Observable signs including bubbling or fizzing (effervescence) due to the release of carbon dioxide gas ($CO_2$).

Everyday Examples of Acid–Carbonate Reactions

Practical examples including mixing vinegar and baking soda, effervescence in baking, and acid rain reacting with marble statues.

Acid–Metal Reaction

A reaction where an acid reacts with a reactive metal higher in the reactivity series (such as zinc or magnesium) to produce hydrogen gas ($H_2$) and a salt.

General Form of Acid–Metal Reaction

Represented as $\text{Acid} + \text{Metal} \rightarrow \text{Salt} + \text{Hydrogen gas}$; for example, $2HCl + Zn \rightarrow ZnCl_2 + H_2$.

Key Indicators of Acid–Metal Reactions

Observable features including hydrogen gas formation and the visible dissolving of the metal.

Everyday Examples of Acid–Metal Reactions

Practical examples including corrosion of metal surfaces, laboratory generation of hydrogen gas, and metal reacting with acidic rainwater.

Combustion Reaction

A chemical reaction where a hydrocarbon reacts with oxygen ($O_2$) to produce carbon dioxide ($CO_2$), water ($H_2O$), and energy.

General Form of Combustion Reaction

Represented as $\text{Hydrocarbon} + O_2 \rightarrow CO_2 + H_2O + \text{Energy}$; for example, methane burning: $CH_4 + 2O_2 \rightarrow CO_2 + 2H_2O$.

Key Indicators of Combustion Reactions

Observable characteristics including heat release, light production, and the formation of carbon dioxide ($CO_2$).

Everyday Examples of Combustion Reactions

Common real-world examples including burning LPG for cooking, gasoline combustion in car engines, and the flame of a candle.