A

Absorber - an absorber does not reflect or transmit particles or radiation that hit it. Aluminium foil is an absorber of alpha particles.  A dark, dull surface is an absorber of infra-red radiation.

Accuracy - is a term that refers to the properties of a measuring instrument. 

Acid - an acid is a chemical that will neutralize a base such as an alkali.  There are many different kinds of acid.   Lemons are sour because they contain citric acid and acid in vinegar is called acetic acid.  It is a substance that disolves in water to form a solution with a pH below 7.  An acid contains hydrogen which can be replaced by a metal to form a salt.  When an acid dissolves in water H+(aq) ions are formed.  A strong acid completely ionises in water and a weak acid only partly ionises.  Common strong acids include hydochloric acid, HCl, sulphuric acid, H2SO4 and nitric acid, HNO3.  A common weak acid is ethanoic acid, CH3COOH.

Acid rain -  is a kind of pollution.  Sulphur and nitrogen oxides are produced from the burning of fossil fuels.  When they escape into the atmosphe, they form sulphuric and nitric acids.  Thes acids cna have effects on our environment, e.g. erode stonework, lower the pH of lakes and rivers killing our wildlife, and cause damage to trees. 

Air - is a mixture of gases.

Alkali - is a metal oxide or hydroxide (base) that dissolves in water to form a solution iwth a pH greater than 7.  An alkali is neutralised by an acid to form a salt and water.  Common alkalis include sodium hydroxide, NaOH, potassium hydroxide, KOH, calcium hydroxide, Ca(OH)2 and ammonium hydroxide, NH4OH.

Alloy - is a metal made bymelting and mixing two or more metals together, e.g. brass is a mixture of copper and zinc and bronze is an alloy of copper and tin.

Amphibians - are animals that live in water and on land.  They have smooth, moist skins and lay their eggs in water.

Apparatus - are the things (equipment) needed to carry out an experiment.

Atom - is the smallest particle of an element which can exist.  The tiniest part of a substance.

B

Bacteria - are very small single-celled  organisms with no nucleus.

Battery - a battery consists of a number of electrical cells.  These cells are usually connected in series to give a highter voltage than that from a sinlge cell.

Biodegradable - is a material that can rot and decay away quickly after we have used it.

Birds - are animals that have feather and wings.  They lay eggs with hard shells and usually fly.

C

Carnivores - are animals that eat other animals.

Catalyst - is something that alters the speed (speeds up) of a chemical reaction or change without being used up at the end of it or permanently changed itself.

Circuit - is one or more conducting paths between the two electrodes of a cell or battery of cells.

Chemicals - are the substances used in chemistry.

Compound - is a substance that has two or more elements in it.

Concave - describes the shape of a lens or other object where the center is thinner than the outside.

Conclusion - things that can be worked out from doing an experiment.

Condensation - is the change from a gas to a liquid or solid.

Conifers - are relating to or part of trees or shrubs that do not have flowers and their seeds are made in cones.

Corrosion - is the wearing away of the surface of a metal by chemical reactions with oxygen and water.  Rusting is one example of corrosion.

Current - is a flow of electric charge.  The current is a metallic conductor is due to a flow of negatively charged electrons. 

D

Dense - made up of very closely packed particles.

Dilute -  is to make a liquid weaker or thinner by adding more liquid, usually more water.

Dispersion - is the splitting of white light into the seven colors of the visible spectrum - rainbow.

Dissolving - is the process that occurs when a solute is added to a solvent and the solute disappears.  The particles of the solute fit between the particles of the solvent.  The solute can be recovered by the evaporation process.  To mix a solid with a liquid so it becomes a liquid as well.

Distillation - this is to separate a liquid from other liquids by boiling it and condensing the steam.

E

Earth - is the planet that we inhabit.  In electricity, the term refers to an electrical connection to the Earth.

Ecosystem - is the sum total of all the living organisms and non-living factors in an environment and the way they interact.

Element - is a pure substance made of one kind of atom.  It cannot be split up into anything simpler without losing its characteristics.  A substance that cannot be separated into simpler substances.

Energy - is transfered by heating by; radiation, conduction and convection.  The amount of energy transfered is measured in joules.

Enzymes - is a substance that speeds up a chemical reaction in the body (a biological catalyst).  Each enzyme works best at a particular temperature and pH.

Erode - is to wear away.

Erosion - is the process where rocks are worn away.

Evaporation - is the process in which a liquid changes to a vapour, due to particles leaving the surface of the liquid.  A liquid turns to a gas.

Evidence - is anything that gives a reason to believe something.

Expand - is when the size of a substance increases due to being heated.  The particles gain energy and move further apart.

Experiment - a test to find something out.  

Explosion - is a very rapid reaction accompanied by a large expansion in gases.

F

Fair Test - is controlling some of the things used or done in a test so they do not change.  An experiment in which only one variable is changed at a time to allow a fair comparison.

Ferns - a plant with strong stems, roota and leaves and do not have seeds.

Filter - is to separate solids (that do not dissolve) from liquids.

Fish - are cold-blooded animals that live in water, they have a backbone, scaly skin, tails and fins for swimming and gills for breathing.

Flowering Plants - any plant that produces flowers and fruit.

Force - is a fush or pull.  Force is measured in units called newtons (N).

Formula - is a way of writing scientific information using letters, numbers and signs.

Friction - occurs when two surfaces move over each other.    Air resistance and water resistnace are friction forces caused by the movement of something through the air or the water.

Freeze - is when you cool something to a very low temperature and it usually forms ice.

Function - is the special purpose or use of something.

G

Galaxy - is a group of millions of stars held together by gravity, like the Milky Way.

Gas - is a state of matter in which the particles move rapidly and are very spread out.

Gravity - is the force of attraction between any two bodies.  It increases with increasing mass of the bodies and decreases if they are further apart.

H

Habitat - is a place where an organism lives.

Herbivores - are animals that eat only plants.

I

Indicator - is a chemical that can show if a substance is acidic or alkaline by changing color.  :ot,is tirms red om acids and blue in alkali.

Insoluble - this is when a solid is unable to dissolve into a liquid.

Invertebrates - are animals without a backbone.

J

Joule (J) - is the unit for measuring energy or work.

K

Kinetic Energy - is the kind of energy in moving things.

L

Lichen - is a mutualistic relationship between a fungus and an alga (simple plant).  They can be seen as crusty patches on tree trunks and walls.

Liquid - is a state of matter in which the particles are close together but randomly arranged.  The particles can move over each other.

M

Magnetic - applies to any object or material that is repelled or attracted by a magnet.  Magnetic materials include iron, steel, cobalt and nickel.

Magnetic field - is an area where a magnetic material experiences a force.  Magnetic fields exist around permanent magnets, electromagnets and electric currents.

Mammals - are animals that are warm-blooded, usually have fur or hair and feed their young with milk from their mother.

Matter - is the material that something is made up of.

Melting - is when a solid changes to a liquid at the melting point by heating.

Melting Point - is when the temperature at which a solid changes to a liquid.

Method - is an orderly way of doing something.

Microbes - are very small living things, usually only one cell big.  A tiny organism that can only be seen with a microscope.  Some microbes can cause disease.

Milky Way - is the spiral galaxy of stars which the Earth is part of.

Mixture - is two or more substances mixed together without actually joining them so that they can be separated again.

Molecule - is a group of atoms joined together.

Moss -  a plant that has weak roots, thin, delicate leaves and do not have seeds.

N

Neutron - is an atomic particle found in the nucleus.  It is similar in mass to a proton buth has no charge.

Newton (N) - is the unit of force.

O

Observations - the things that can be seem during an experiment.

Omnivores - are animals that eat both animals and plants.

Opaque - does not allow light through.

Orbit - the curved path taken by an object that moves round another object like a planet around the Sun

P

Particles - are the tiny parts that scientists believe everything is made up of.

Photosynthesis - is the process from which plants use or changes sunlight into energy from the sun to make their own food.  This energy is their food which contains oxygen and glucose.  [carbon dioxide + water = glucose + oxygen]

Physical Change - is when you mix two substances and their particles become jumbled up together.  They do not necessarily combine chemically unless the atoms inthe molecules are rearranged - this change is physical change only.  This new substance is called a mixture and can usually be separated quite easily.

Planet - is a large body that orbits a star.

Plates - are huge sections of the Earth's crust which float on the mantle.

Pole - in magnetism, the strongest part of a magnet. The pole of a magnet that points towards magnetic North is calle dits North seeking pole.

Process - is a number of actions for making or doing something.

Properties - are what a material or substance is like and how it behaves.  Describes how a substance behaves.

Proton - is an atomic particle found in the nucleus.  It is similar in mass to the neutron but has a positive charge.

Q

R

Ray - is a narrow beam of light.

Reaction - is something that happens in response to something else.

Reaction Time - is the time that elapses between an event occurring and aperson responding to the event.

Recycled - is when something is used again in a system.

Reflect - is to bounce something back from a surface.

Reflection - is the change in direction when light or other wave motion rebounds at a boundary between two materials. 

Refraction - is the change in speed when light or other wave motions passes from one material into another. The change in speed causes a change in wavelength and may cause a change in direction.

Reliable - things that can be taken to be true.

Reptiles -  are animals that live mainly on land and lay eggs with soft shell.  They havedry, scaly skin.

Residue - is something that remains behind or is left over.

Result - is what happens at the end of an experiment.

Rusting - is an oxidation process of iron and steel.   Iron and steel rust in the presence of oxygen (air) and water.   Rust is hydrated iron(III) oxide.  Rust damages metal parts so it is important to try to prevent it.  One way is to alloy the iron and steel with other metals which resist rust.  Stainless steel is an alloy of iron wiht other metals such as chromium and nickel.  Tpresence of these other metals protects the stainless steel from corrosion and allows these metals to be used as kitchen sinks and cutlery.

S

Sieve - is when you separate a solid or a liquid by using a sieve.

Solar System - is a star and all the objects that orbit it.

Soluble - is the liquid that is produced after you have dissolved a solid into another liquid.

Solution - is the mixture formed when a solute dissoves in a solvent.

Star - is an astronomical object that generates energy due to nuclear fusion.  A star gives out light and/or other forms of electromagnetic radiation.

Static Electricity - is an unbalanced charge that is not moving.  A common cause of static electricit is the transfer of electrons when two objects are rubbed together.  The object that gains electrons becomes charged negatively while the object that loses electrons becomes charged positively.

Sun - is the Earth's star.

T

Temperature - is a measure of how hot an object is.

U

Universe - is everything that exists.

V

Variables - are the things that can change during an experiment.

Vertebrates - are animals with a backbone.

W

Weight - is a force due to gravity acting on an object.

X

X-rays - are used to detect broken bones.  very penetrating, short wavelength electromagnetic waves.

Y

Z

 

 

 

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