Chemistry: Reactions, Thermodynamics, Kinetics, and Metal Reactivity

Vocabulary flashcards covering chemical equations, reaction types, thermochemistry, solubility, metal reactivity, and reaction kinetics based on lecture notes.

Chemical Equation

A symbolic way of representing a chemical reaction consisting of four main components: reactants, products, reaction direction, and physical states of each component.

Physical States in Chemical Equations

Notation used in chemical equations to represent physical form: $(s)$ for Solid, $(l)$ for Liquid, $(g)$ for Gas, and $(aq)$ for Aqueous Solution.

Law of Conservation of Mass

A fundamental law stating that matter cannot be created or destroyed in a chemical reaction; thus, the total mass of reactants equals the total mass of products, and all reactant elements must appear in the products.

C-H-O Method

A specific sequence of balancing rules used for combustion reactions that balances Carbon first, Hydrogen second, and Oxygen last.

Chemical Reaction

A process that always involves the formation of a new substance, indicated by observations such as a substance disappearing, gas release, solid precipitation, colour change, temperature change, new odour, or light emission.

Physical Reaction

A process that differs from a chemical reaction by only involving a change of state, such as solid to liquid, liquid to gas, or solid to gas.

Combination Reaction

A reaction occurring when two substances react to form a single substance, written as $A + B \rightarrow C$.

Decomposition Reaction

A reaction in which one substance is broken down into two or more substances.

Single Displacement Reaction

A reaction in which one element in a compound is replaced by another reactant, written as $AB + C \rightarrow AC + B$.

Double Displacement Reaction

A reaction where two substances swap ions, written as $AB + CD \rightarrow AD + CB$, which includes neutralisation and precipitation reactions.

Neutralisation Reaction

A type of double displacement reaction in which an acid and a base react to form a salt and water.

Combustion Reaction

A reaction where a hydrocarbon containing $H$ and $C$ reacts with Oxygen to form water and carbon dioxide, represented as $A + O_2 \rightarrow H_2O + CO_2$.

System (Thermodynamics)

The specific group of reacting molecules being studied in a chemical process.

Surroundings

Everything in the universe that exists outside the designated chemical system.

Universe (Thermodynamics)

The complete thermodynamic environment, defined as the system plus the surroundings.

Exothermic Reaction

A chemical reaction that releases heat into the surroundings, resulting in products that have less energy in their bonds than the reactants.

Endothermic Reaction

A chemical reaction that absorbs heat from the surroundings, resulting in products that have more energy in their bonds than the reactants.

Enthalpy ($\Delta H$)

A thermodynamic property that measures the net change in heat energy during a reaction; positive for endothermic reactions and negative for exothermic reactions.

Activation Energy

The minimum amount of energy required for colliding particles to initiate a chemical reaction.

Soluble

Represented by $(s)$ in solubility tables, denoting a substance that dissolves in water.

Insoluble

Represented by $(I)$ in solubility tables, denoting a substance that does not dissolve in water.

Sparingly Soluble

Represented by $(SS)$ in solubility tables, denoting a substance that barely dissolves in water.

Precipitation Reaction

A reaction that produces an insoluble solid precipitate.

Reaction of Metal with Water

A single displacement reaction represented by $\text{Metal} + \text{Water} \rightarrow \text{Metal Oxide (or Hydroxide)} + \text{Hydrogen}$.

Reaction of Metal with Oxygen

A combination reaction represented by $\text{Metal} + \text{Oxygen} \rightarrow \text{Metal Oxide}$, which occurs during metal rusting.

Reaction of Metal with Acid

A reaction represented by $\text{Metal} + \text{Acid} \rightarrow \text{Salt} + \text{Hydrogen}$, where metals generally react more vigorously than with water.

Reactivity Series of Metals

An experimentally created ordering of metals by reactivity, featuring Group 1 metals at the top and transition metals at the bottom.

Metal Displacement Reaction

A reaction in which a more reactive metal displaces a less reactive metal from its compound.

Particle Collision Theory

A theory stating that constantly moving particles must collide with sufficient activation energy for a chemical reaction to take place.

Rate of Reaction

A measure of how quickly the mass of the reactants decreases or how quickly the mass of the product increases over time.