Matter and Reactions

Comprehensive practice flashcards covering states of matter, particle theory, phase transitions, atomic structure, subatomic particles, electron configurations, ions, and the periodic table.

Matter

Anything that has mass and takes up space.

Solid

A state of matter in which particles are packed together closely in a fixed shape, vibrating in place under very strong attractive forces.

Liquid

A state of matter in which particles are packed closely together but can slide past one another, held together by moderate forces that are less strong than those in a solid.

Gas

A state of matter characterized by lots of space between particles that move around quickly with large amounts of energy and have no forces holding them together.

Three States of Matter (Particle Model)

A conceptual model illustrating the packing and movement of particles in solid, liquid, and gas phases within closed containers.

Fixed Shape

A physical property possessed exclusively by solids among the three states of matter, meaning the substance maintains a rigid, definite form.

Fixed Volume

A physical property shared by solids and liquids, meaning their total occupied space remains constant regardless of the container.

Compressibility

The property of being able to be squeezed into a smaller volume; gases are fairly easy to compress due to large spaces between particles, whereas solids and liquids cannot be compressed easily.

Fluidity (Flow)

The ability of particles to slide past one another and pour smoothly; a property possessed by liquids and gases, but not solids.

Particle Packing in Solids

Particles are arranged closely together in a rigid, fixed pattern and vibrate gently without moving apart.

Particle Packing in Liquids

Particles are packed closely together but are free to slide past one another, allowing the substance to flow and take the shape of its container.

Particle Packing in Gases

Particles have lots of space between them and move rapidly in random directions, completely filling any container.

Particle Forces in Solids

Very strong attractive forces that hold the constituent particles firmly in fixed positions.

Particle Forces in Liquids

Moderate attractive forces that hold particles together loosely, allowing them to remain close while sliding over one another.

Particle Forces in Gases

Non-existent forces holding particles together, allowing gas particles to move completely freely.

Examples of Solids

Substances such as ice, chocolate, and sugar that hold a fixed shape and fixed volume.

Examples of Liquids

Substances such as water, coffee, and fruit juice that have a fixed volume but take the shape of their container.

Examples of Gases

Substances such as steam, oxygen, and hydrogen that have neither a fixed shape nor a fixed volume.

Melting Point

The specific temperature at which a solid turns into a liquid, during which the temperature remains constant while heat is supplied.

Boiling Point

The specific temperature at which a liquid turns into a gas, during which the temperature remains constant while heat is supplied.

Melting Point of Water

The temperature ($0\,^\circ\text{C}$) at which solid ice melts into liquid water, and conversely at which water solidifies.

Boiling Point of Water

The temperature ($100\,^\circ\text{C}$) at which liquid water turns into steam, and conversely at which steam condenses.

Solidification (Freezing)

The change of physical state from a liquid to a solid as thermal energy is removed.

Evaporation

The change of physical state from a liquid to a gas as heat is supplied.

Condensation

The change of physical state from a gas to a liquid as the substance cools.

Heating Curve of Water

A graph showing temperature changes against heat supplied, illustrating constant-temperature plateaus at the melting point and boiling point.

Atom

The smallest particle of matter that can exist, functioning as the foundational building block of all matter.

Subatomic Particles

The fundamental particles that make up the interior structure of an atom: protons, neutrons, and electrons.

Nucleus (Atomic)

The dense central core of an atom where protons and neutrons are located.

Proton

A positively charged subatomic particle found in the nucleus with a relative charge of $+1$ and a relative mass of $1$.

Neutron

A neutral subatomic particle located in the nucleus with a charge of $0$ and a relative mass of $1$.

Electron

A negatively charged subatomic particle found orbiting around the nucleus in shells, possessing a charge of $-1$ and negligible relative mass.

Relative Charge of a Proton

The electric charge value of $+1$ assigned to a proton.

Relative Charge of an Electron

The electric charge value of $-1$ assigned to an electron.

Relative Charge of a Neutron

The electric charge value of $0$ assigned to a neutron, indicating that it is electrically neutral.

Relative Mass of a Proton

A standardized mass value of $1$ unit.

Relative Mass of a Neutron

A standardized mass value of $1$ unit, equal to that of a proton.

Relative Mass of an Electron

Described as very small, negligible, or nearly zero relative to protons and neutrons.

Location of Protons and Neutrons

Both protons and neutrons are exclusively located together inside the nucleus of an atom.

Location of Electrons

Electrons are located orbiting in electron shells outside and around the nucleus.

Neutralisation of Subatomic Charges

A proton will neutralise the negative charge on an electron, and an electron will neutralise the positive charge on a proton.

Electrostatic Attraction in Atoms

The attractive force exerted between opposite charges, such as a positively charged proton attracting a negatively charged electron.

Electrostatic Repulsion in Atoms

The repulsive force exerted between particles of identical charge, such as two protons repelling each other.

Neutral Atom

An atom that carries no net charge because its total number of positive protons equals its total number of negative electrons.

Atomic Number

The number that tells us the quantity of protons (or electrons in a neutral atom) contained within the atom.

Electron Shells

Specific orbital regions outside the nucleus where electrons are arranged around an atom.

Maximum Capacity of the First Electron Shell

The innermost electron shell can hold a maximum of $2$ electrons.

Maximum Capacity of the Second Electron Shell

The second electron shell can hold a maximum of $8$ electrons.

Maximum Capacity of the Third Electron Shell

The third electron shell holds up to $8$ electrons for the first 20 elements.

Electron Configuration Notation

A written numerical shorthand representing the arrangement of electrons per shell separated by commas, such as $2,8,8$.

Valence Shell

The outermost electron shell of an atom.

Valence Electrons

Electrons located in the outermost shell that determine how chemically reactive an atom is going to be.

Chemical Reactivity

The tendency of an atom to undergo chemical change, governed by the number of electrons situated in its outer valence shell.

Ion

An atom that has gained or lost one or more electrons, thereby obtaining an overall electric charge.

Cation

A positively charged ion formed when a neutral atom loses one or more valence electrons.

Anion

A negatively charged ion formed when a neutral atom gains one or more electrons.

Reason for Ion Formation

Atoms gain or lose electrons in order to obtain a full valence (outer) shell and become chemically stable.

Electron Configuration of Hydrogen ($\text{H}$)

Written as $1$, indicating $1$ proton and $1$ electron in its first shell.

Electron Configuration of Helium ($\text{He}$)

Written as $2$, containing a complete first electron shell.

Electron Configuration of Lithium ($\text{Li}$)

Written as $2,1$, with $2$ electrons in the first shell and $1$ valence electron in the second shell.

Electron Configuration of Beryllium ($\text{Be}$)

Written as $2,2$, having an atomic number of $4$.

Electron Configuration of Boron ($\text{B}$)

Written as $2,3$, possessing an atomic number of $5$.

Electron Configuration of Carbon ($\text{C}$)

Written as $2,4$, having an atomic number of $6$ with $2$ electrons in the first shell and $4$ in the second shell.

Electron Configuration of Nitrogen ($\text{N}$)

Written as $2,5$, having $7$ total electrons ($2$ in shell 1 and $5$ in shell 2).

Electron Configuration of Oxygen ($\text{O}$)

Written as $2,6$, having an atomic number of $8$.

Electron Configuration of Fluorine ($\text{F}$)

Written as $2,7$, containing $7$ valence electrons and needing $1$ electron to achieve a full shell.

Electron Configuration of Neon ($\text{Ne}$)

Written as $2,8$, featuring a completely filled second shell.

Electron Configuration of Sodium ($\text{Na}$)

Written as $2,8,1$, having $11$ total electrons and $1$ electron in its outer valence shell.

Electron Configuration of Magnesium ($\text{Mg}$)

Written as $2,8,2$, possessing an atomic number of $12$.

Electron Configuration of Aluminium ($\text{Al}$)

Written as $2,8,3$, containing $13$ total electrons ($2$ in shell 1, $8$ in shell 2, and $3$ in shell 3).

Electron Configuration of Silicon ($\text{Si}$)

Written as $2,8,4$, possessing an atomic number of $14$.

Electron Configuration of Phosphorus ($\text{P}$)

Written as $2,8,5$, possessing an atomic number of $15$.

Electron Configuration of Sulfur ($\text{S}$)

Written as $2,8,6$, possessing an atomic number of $16$.

Electron Configuration of Chlorine ($\text{Cl}$)

Written as $2,8,7$, containing $7$ valence electrons and needing $1$ electron to achieve a stable octet.

Electron Configuration of Argon ($\text{Ar}$)

Written as $2,8,8$, having a full outer shell which makes it stable and unreactive.

Electron Configuration of Potassium ($\text{K}$)

Written as $2,8,8,1$, having an atomic number of $19$.

Electron Configuration of Calcium ($\text{Ca}$)

Written as $2,8,8,2$, having an atomic number of $20$.

Element

A pure substance that is made up of only ONE type of atom.

Compound

A substance formed when two or more different types of atoms are chemically bonded together.

Mixture

A material composed of two or more different substances that are physically mixed rather than chemically joined.

Elemental Abundance in the Earth's Crust and Human Body

Pie chart comparisons showing the elemental breakdown of the Earth's Crust and the Human Body.

Abundance of Oxygen in Earth's Crust

Oxygen constitutes $49.5\%$ of the Earth's crust by mass, making it the most abundant element.

Abundance of Silicon in Earth's Crust

Silicon accounts for $25.7\%$ of the Earth's crust by mass, ranking as the second most abundant element.

Abundance of Aluminum in Earth's Crust

Aluminum comprises $7.5\%$ of the Earth's crust by mass.

Abundance of Iron in Earth's Crust

Iron comprises $4.7\%$ of the Earth's crust by mass.

Abundance of Calcium in Earth's Crust

Calcium comprises $3.4\%$ of the Earth's crust by mass.

Abundance of Oxygen in the Human Body

Oxygen constitutes $65\%$ of the human body by mass, making it the most abundant element in our bodies.

Abundance of Carbon in the Human Body

Carbon makes up $18\%$ of the human body by mass.

Abundance of Hydrogen in the Human Body

Hydrogen makes up $10\%$ of the human body by mass.

Hydrogen in the Universe

The most common element in the universe and the primary component of stars, including the Sun.

Nuclear Fusion in Stars

Reactions inside the Sun and stars that transform hydrogen into helium, releasing massive amounts of energy essential for life on Earth.

Silicon

An element similar to carbon that forms most above-ground rocks and molten magma below ground, and serves as an essential material in computer components.

Sand

A substance composed of a combination of silicon and oxygen that can melt into glass when heated.

Chemical Symbol Rules

Symbols consist of one or two letters derived from the element's English or Latin name; the first letter is always capitalized, and any subsequent letter is lowercase.

Periodic Table

A comprehensive chart that organizes all chemical elements by atomic number and recurring chemical and physical properties.

Groups and Periods (Periodic Table)

Diagrammatic representation showing vertical columns designated as groups and horizontal rows designated as periods.

Groups (Periodic Table)

The vertical columns (downwards) of the periodic table, grouping elements that share similar valence configurations and chemical properties.

Periods (Periodic Table)

The horizontal rows (across) of the periodic table, representing elements that share the same number of occupied electron shells.

Location of Metals

Found on the left side and center of the periodic table.

Location of Non-metals

Found clustered on the right side of the periodic table (along with hydrogen).