Dictionary Assignment By John Li 11 A

Qualitative Information  Data can be observed but not measured  For example, today is very hot is one of the qualitative information

Quantitative Information  Data which can be measured  For example, 42 ℃ is one kind of quantitative information

Observation  Use one of one or more senses to gather the information  Observation of natural phenomena

Interpretation  The action of explaining the meaning of something  Children often give different interpretations of the experiments

Description  A spoken or written account of some details during the experiments  We should write the description during the experiments

Data  Facts that collected during the experiments  Record the data is one of the most important processes during the experiments

Experiment  Procedure undertaken to make a discovery  We can test out theories by experiments

Hypothesis  A proposes explanation made on the basis of limited (the result is uncertain.)  We should raise a hypothesis before the experiment

Theory  A supposition of ideas intended to explain something （ result is certain. ）  Darwin’s theory of evolution is one of the theory

Law  It explains things, but they do not describe them.  Consider Newton's law of gravity

Matter  The physical substance in general  The entire universe is mad of different kinds of matters

Physical Property  Color, shape, mass, volume, density weight  Malleability, ductility  Boiling point, melting point  We can get the physical property by our eyes

Chemical Property  It is any of a material's properties that becomes evident during, or after, a chemical property  Flammability is one of chemical property.

Extensive Property  It depend on the amount of matter that is present.  Extensive property include volume and mass

Intensive Property  It does not depend on the amount of matter that is present  Intensive property include boiling point and density

Solids  Firm and stable in shape  Melted wax becomes solid when it cools

Liquids  A substance that flows freely but is of constant volume.  Water is one of the liquids

Gases  An air-like fluid substance which expands freely to fill any space available  Oxygen is gas at ordinary temperature

Hardness  Hardness is the ability of a solid to resist abrasion or scratching  We know the hardness of ice, so we can walk on this frozen lake

Malleability  Malleability is the ability to be rolled or hammered into thin sheets  This object is solid but it has malleability

Ductility  Ductility is the ability to be stretched or drawn into wires  The iron wire has the great ductility

Luster  Luster is the manner in which a solid surface reflects light  This is a pearl with a beautiful luster

Viscosity  Viscosity is the resistance of fluid to flow  Different kinds of fluid have different viscosities

Diffusion  Diffusion is the intermingling of fluids as a result of motion within the fluid  The diffusion between water and vinegar

Vapour  Vapour is the gaseous material formed by the evaporation of a substance which boils above room temperature  When we are boiling water, there will be many water vapour

Element  An element is a substance which cannot be separated into simpler substances as a result of any chemical process  Hydrogen and oxygen are elements, but water is not

Atom  The smallest particle of a chemical element that can exist  For example, Ag is one of the atoms

Molecule  A group of atoms bonded together  For example, H2O is one of the molecules

Ion  An atom or molecule with a net electric charge due to the loss or gain of one or more electrons  For example, NO3- is one of the Ions

Particle  Used to describe a small bit of matter such as an atom, molecule and iron  There are many particles around our life, it is unhealthy for us

Homogenous Substance  The substance consisting of only one phase  For example, water is one of the homogenous substances

Heterogeneous substance  The substance consisting of more than one phase  For example, pencil is one of the heterogeneous substances

Pure Substance  The substance is homogeneous and has an unchangeable composition  For example, sugar is one of the pure substances

Mixture  A substance made by mixing other substances together  When salt dissolved in water, it will be mixture

Mechanical Mixture  A heterogeneous mixture of two or more substances  For example, desk is one of the mechanical mixture

Solution  It is a homogeneous mixture of two or more substances  Solution includes solvent and solute

solvent  Able to dissolve other substances  Water is one of the solvent

Solute  The substance that able to be dissolved by other solvents  When salt is dissolved into water, the salt is solute

Compound  A thing that is composed of two or more separate elements  For example, salt(sodium chloride) is one of the compound

Homogenous Mixture  Changeable composition, but each particular composition has unchanging, uniform physical properties  Coffee is the example of the homogenous mixture

Heterogeneous Mixture  Each component present has different physical properties, regardless of composition  When oil mix into water, it will become heterogeneous mixture

Filtration  Allow the separation of liquids from solids  We can use filtration to clean water

Filtrate  A liquid which has passed through a filter  The filtrate is cleaner than before

Residue  A substance that remains after a process such as combustion or evaporation  Residue is solid.

Distillation  The separation to separate liquid-in-liquid solution  the distillate is the result during the distillation

Solvent Extraction  Extraction of a dissolved liquid or solid from a liquid solution  We can use solvent extraction to separate liquid-in-liquid solution

Recrystallization  It is a variation on the method of evaporation in which the solid in a solid-in- liquid solution is separated in a pure and crystalline stated  We can get crystalline during the recrystallization

Gravity Separation  Used to separate desired solids from a mechanical mixture(based on their density)  We can use gravity separation to separate the juice, such as watermelon juice

Chromatography  An apparatus for performing chromatography  We should use alcohol to do the chromatography

Chemical Change  It is a change which create new substances  There is chemical change during the burning

Physical Change  It is change in which do not create new substance  Melting is one of the physical change

Kinetic Energy  It is energy that many molecules’ motion  There are three types of kinetic energy, they are rotational energy, vibrational energy and translation energy

Rotational Energy  Causes a molecule to rotate around one of its axes  Centre of rotation is one of the rotational way

Vibrational Energy  Changes the bond lengths and angles between atoms in a molecule  It can move freer than rotational energy

Translational Energy  Causes the molecule to travel in a straight line from place to place  It can lets molecules move to anyplaces