Types of Chemical Reactions

Practice vocabulary flashcards defining core terms, reaction classifications, and redox concepts from the Lesson 1 Types of Chemical Reactions lecture notes.

Chemical Reaction

The process in which bonds are broken in molecules of reactants, and new bonds are formed in molecules of the products.

Direct Combination Reactions

Reactions in which two or more substances combine to form a single new compound, generalized as $A + B \rightarrow AB$.

Decomposition Reactions

Reactions in which some compounds decompose into simpler components, using a form of energy such as heat or light.

Thermal Decomposition of Metal Oxides

Reactions in which certain metal oxides decompose upon heating into the metal and oxygen gas, such as $2\text{HgO}_{(s)} \xrightarrow{\Delta} 2\text{Hg}_{(l)} + \text{O}_{2(g)}$.

Thermal Decomposition of Metal Carbonates

Reactions in which certain metal carbonates decompose upon heating into a metal oxide and carbon dioxide gas, such as $\text{CaCO}_{3(s)} \xrightarrow{\Delta} \text{CaO}_{(s)} + \text{CO}_{2(g)}$.

Single Replacement Reactions

Reactions in which an element replaces another element in one of its compounds, generalized as $A + BC \rightarrow AC + B$.

Chemical Reactivity Series

The arrangement of metal elements in a descending order according to their degree of chemical reactivity.

Double Replacement Reactions

Reactions in which the cations and anions of two ionic compounds, usually in aqueous solutions, exchange their positions to form two new compounds, generalized as $AB + CD \rightarrow AD + CB$.

Neutralization Reaction

The reaction of an acid with an alkali to form a salt and water ($\text{Acid} + \text{Alkali} \rightarrow \text{Salt} + \text{Water}$).

Precipitation Reactions

Reactions that occur between two salt solutions and are associated with the formation of a precipitate, which is a solid substance that does not dissolve in water.

Universal Indicator

A chemical indicator whose colour changes according to the acidity or alkalinity of the solution to which it is added, showing red in strong acids, green at the neutral point, and violet in strong alkalis.

Hard Water

Groundwater that contains high percentages of calcium and magnesium salts, which can lead to scale deposits inside pipes, water heaters, and washing machines.

Oxidation (Traditional Concept)

A chemical process that results in an increase in the percentage of oxygen or a decrease in the percentage of hydrogen in a substance.

Reduction (Traditional Concept)

A chemical process that results in a decrease in the percentage of oxygen or an increase in the percentage of hydrogen in a substance.

Oxidation (Electronic Concept)

A chemical process in which an atom or an ion loses one or more electrons.

Reduction (Electronic Concept)

A chemical process in which an atom or an ion gains one or more electrons.

Reducing Agent (Electronic Concept)

The substance that loses one or more electrons during a chemical reaction, thereby undergoing oxidation.

Oxidizing Agent (Electronic Concept)

The substance that gains one or more electrons during a chemical reaction, thereby undergoing reduction.

Chemical reaction

The process in which bonds are broken in molecules of reactants, and new bonds are formed in molecules of the products.

Direct combination reactions

Reactions in which two or more substances combine to form a new compound, following the general pattern $A + B \rightarrow AB$.

Decomposition reactions

Reactions in which some compounds decompose into simpler components using a form of energy such as heat or light, following the general pattern $AB \rightarrow A + B$.

Thermal decomposition of metal oxides

A reaction in which certain metal oxides decompose upon heating into the constituent metal and evolved oxygen gas ($O_2$).

Thermal decomposition of metal carbonates

A reaction in which certain metal carbonates decompose upon heating into a metal oxide and evolved carbon dioxide gas ($CO_2$).

Single replacement reactions

Reactions in which an element replaces another element in one of its compounds, following the general form $A + BC \rightarrow AC + B$.

Chemical reactivity series

The arrangement of metal elements in a descending order according to their chemical reactivity.

Double replacement reactions

Reactions in which the cations and anions of two ionic compounds, usually in aqueous solutions, exchange their positions to form two new compounds, represented as $AB + CD \rightarrow AD + CB$.

Neutralization reaction

A double replacement reaction between an acid and an alkali that produces a salt and water.

Precipitation reactions

Reactions occurring between two salt solutions that are associated with the formation of an insoluble solid precipitate.

Universal indicator

A chemical indicator whose colour changes according to the acidity or alkalinity of the solution, showing red in strong acid, green in neutral, and violet in strong alkali.

Hard water

Groundwater that contains high percentages of dissolved calcium and magnesium salts, which forms mineral scale deposits inside pipes and heaters.

Silver sulphide

The black substance formed as a surface layer on silverware and utensils as a result of their reaction with atmospheric air.

Oxidation (traditional concept)

A chemical process that results in an increase in the percentage of oxygen or a decrease in the percentage of hydrogen in a substance.

Reduction (traditional concept)

A chemical process that results in a decrease in the percentage of oxygen or an increase in the percentage of hydrogen in a substance.

Oxidation process (electronic concept)

A chemical process in which an atom or an ion loses one or more electrons.

Reduction process (electronic concept)

A chemical process in which an atom or an ion gains one or more electrons.

Reducing agent (electronic concept)

The substance that loses one or more electrons during a chemical reaction and thereby undergoes oxidation.

Oxidizing agent (electronic concept)

The substance that gains one or more electrons during a chemical reaction and thereby undergoes reduction.