Science

Methane

CH4

Ethane

C2H6

Propane

C3H8

Butane

C4H10

Pentane

C5H12

Hexane

C6H14

Heptane

C7H16

Octane

C8H18

Ethene

C2H4

Propene

C3H6

Butene

C4H8

Pentene

C5H10

Hexene

C6H12

Heptene

C7H14

Octene

C8H16

Alkenes

Unsaturated hydrocarbons because they contain a double bond

Alkanes

Saturated hydrocarbons because they only contain single bonds

Ionic bonding

Bonding between metal and non-metal atoms

Covalent bonding

Bonding between non-metal atoms only

Metallic bonding

Bonding between metal atoms only

Alcohols

Organic molecules with an OH functional group called hydroxyl

Boiling point

The more carbon atoms in a hydrocarbon, the higher its boiling point

Balancing equations

You cannot have half atoms

Methene

Does not exist

Miscible

Two liquids that dissolve in each other

Immiscible

Two liquids that do not dissolve in each other

Intermolecular forces

Forces of attraction between molecules

Polymerisation

A reaction joining monomers into long chains to form a polymer

Ocean acidification

Lowering of ocean pH due to increased CO2 in the atmosphere

Speed

The rate at which distance is covered

Velocity

Speed in a specific direction

Speed formula

v = change in distance / change in time

Distance-time graph

Shows distance against time

Gradient of distance-time graph

Shows the speed of an object

Distance-time graph features

Constant speed, stationary, acceleration and deceleration

Acceleration

When an object changes its speed

Positive acceleration

Speed is increasing

Negative acceleration

Speed is decreasing

Change in speed

Final speed minus initial speed

Acceleration formula

a = change in speed / change in time

Speed-time graph

Shows how speed changes over time

Gradient of speed-time graph

Shows acceleration

Area under speed-time graph

Shows distance travelled

Speed-time graph features

Constant acceleration, constant speed and constant deceleration

Rectangle area

Height x width

Triangle area

1/2 x base x height

Contact forces

Forces caused by physical contact between objects

Non-contact forces

Forces that act without objects touching, such as gravity and magnetism

Force

A push or pull on an object

Balanced forces

Equal forces acting in opposite directions

Unbalanced forces

Unequal forces that cause acceleration

Speed unit

Metres per second (m/s)

Distance unit

Metres (m)

Time unit

Seconds (s)

Acceleration unit

Metres per second squared (m/s^2)

Force unit

Newtons (N)

Net force

The overall force acting on an object

Newton's First Law

An object stays at rest or constant velocity unless acted on by an unbalanced force

Newton's Second Law

Acceleration depends on mass and applied force

Newton's Third Law

Every action force has an equal and opposite reaction force

Force formula

F = ma

Mass

The amount of matter in an object

Weight

The effect of gravity on an object's mass

Gravity on Earth

10 m/s^2

Drag

Resistance caused by air or water moving over a surface

Friction

A force that opposes motion between surfaces

Pressure

Force exerted per unit area

Pressure formula

P = F/A

More surface area

Pressure becomes more spread out and weaker

Less surface area

Pressure becomes more concentrated and stronger

Net force equals zero

Object is at rest or moving at constant velocity

Net force not equal to zero

Object accelerates

Time formula for speed

t = change in distance / speed

Distance formula

d = speed x time

Speed formula from acceleration

v = acceleration x time

Time formula for acceleration

t = change in speed / acceleration

Density

Mass per unit of volume

Density formula

Density = mass / volume

Gravitational potential energy

Energy an object has due to its height above Earth

Kinetic energy

Energy an object has due to its motion

Gravitational potential energy formula

Ep = mgh

Kinetic energy formula

Ek = 1/2mv^2

Power

The rate at which work is done

Work

Force moving an object a certain distance

Work formula

W = F x d

Power formula

P = W/t

Monohybrid inheritance

Inheritance of a characteristic controlled by one gene

Mutation

A permanent change to the base sequence of a gene

Mutagens

Physical or chemical agents that cause mutations in DNA

Catalyst

A substance that speeds up a chemical reaction without being used up