Year 10 Physics and Chemistry Exam Key Concepts

Atomic structure

The arrangement of protons, neutrons, and electrons in an atom, where protons and neutrons are located in the nucleus, and electrons orbit around the nucleus.

Valency electrons

Electrons in the outermost shell of an atom that are involved in forming chemical bonds.

Electron configuration

The distribution of electrons in an atom's electron shells and subshells.

Core charge

The effective nuclear charge experienced by an electron in an atom, calculated as the number of protons minus the shielding effect of inner-shell electrons.

Electronegativity

A measure of an atom's ability to attract and hold onto electrons in a chemical bond.

Ionisation energy

The energy required to remove an electron from an atom or ion in its gaseous state.

Atomic radius

The distance from the nucleus of an atom to the outer boundary of its electron cloud.

Metallic properties

Characteristics of metals, such as conductivity, malleability, ductility, and luster.

Non-metallic properties

Characteristics of non-metals, such as poor conductivity, brittleness, and lack of luster.

Octet Rule

The principle that atoms tend to bond in such a way that they have eight electrons in their valence shell, achieving a stable electron configuration.

Covalent compounds

Chemical compounds formed by the sharing of electrons between atoms.

Ionic compounds

Chemical compounds formed by the transfer of electrons from one atom to another, resulting in the formation of charged ions.

Bohr model

A diagram representing the structure of an atom, showing electrons in fixed orbits around the nucleus.

Lewis dot structures

Diagrams that represent the valence electrons of atoms within a molecule, using dots around the chemical symbol.

Chemical reaction components

The substances that undergo change (reactants) and the substances formed (products) during a chemical reaction.

Combination reaction

A type of chemical reaction where two or more substances combine to form a single product.

Decomposition reaction

A type of chemical reaction where a single compound breaks down into two or more simpler substances.

Single displacement reaction

A chemical reaction where one element replaces another element in a compound.

Neutralisation reaction

A chemical reaction between an acid and a base that produces water and a salt.

Precipitation reaction

A chemical reaction that results in the formation of an insoluble solid (precipitate) when two solutions are mixed.

Combustion reaction

A chemical reaction that occurs when a substance combines with oxygen, releasing energy in the form of heat and light.

Rusting

A chemical reaction involving the oxidation of iron in the presence of water and oxygen, resulting in the formation of iron oxide (rust).

Balancing chemical equations

The process of ensuring that the number of atoms for each element is the same on both sides of a chemical equation.

Solubility of ionic compounds

The ability of ionic compounds to dissolve in water, which can be determined by various factors including temperature and the nature of the ions.

Straight line motion

The motion of an object moving in a straight path, characterized by distance, speed, velocity, and acceleration.

Vector quantity

A quantity that has both magnitude and direction, such as velocity or force.

Scalar quantity

A quantity that has only magnitude and no direction, such as speed or mass.

SUVAT equations

Equations used to calculate motion with constant acceleration, relating displacement, initial velocity, final velocity, acceleration, and time.

Distance-time graph

A graph that shows the distance traveled by an object over time.

Velocity-time graph

A graph that shows the velocity of an object over time, indicating acceleration or deceleration.

Newton's First Law of Motion

An object at rest stays at rest, and an object in motion stays in motion unless acted upon by a net external force.

Inertia

The tendency of an object to resist changes in its state of motion.

Balanced force

Forces that are equal in size and opposite in direction, resulting in no change in motion.

Unbalanced force

Forces that are not equal and opposite, resulting in a change in motion.

Resultant force

The overall force acting on an object, calculated by vector addition of all individual forces.

Newton's Second Law of Motion

The acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass (F=ma).

Weight

The force exerted by gravity on an object, calculated as the product of mass and gravitational acceleration (W=mg).

Newton's Third Law of Motion

For every action, there is an equal and opposite reaction.

Momentum

The product of an object's mass and its velocity, representing the quantity of motion an object has.

Impulse

The change in momentum of an object when a force is applied over a period of time.

Work

The energy transferred when a force is applied to an object over a distance, calculated as W=Fd (force times distance).

Gravitational potential energy

The energy an object possesses due to its position in a gravitational field, calculated as PE=mgh (mass times gravitational acceleration times height).

Kinetic energy

The energy an object possesses due to its motion, calculated as KE=1/2 mv² (one-half mass times velocity squared).

Energy transformations

The process of changing energy from one form to another, such as from gravitational potential energy to kinetic energy.