Substances And Reactions Flashcards
(33 cards)
Solids
- holds shape
- Fixed volume
(Has shape and volume)
Methods of classifying substances
- solids, liquids, and gases
- elements, mixtures, and compounds
- metals, non-metals, and semi-metals
Liquids
- shape of container
- free surface
- fixed volume
- has volume but adopt shape of container
Gases
- Shape of container
- Volume of Container
- occupies the shape and volume of container
How do substances change their state?
- matter, solid, and gases exist because each has a different balance of kinetic and potential energy. When energy is added or removed, it changes state
What is matter composed of? Be specific.
Matter is composed of particles. - atoms - ions - molecules (Pneumonic: particles have good AIM)
Interatomic Forces
How particles attract each other
What does the state of matter depend on?
Balance between:
- kinetics energy of particles (tending to separate)
- attraction between particles (tending to pull together)
Element
- Pure Substance
- Contains only one atom
- represented by symbols on period table
- can be classified as metals, non metals, and semi-metal (metalloids
Metalloid
Otherwise known as a semi-metal
Metals
- shiny appearance
- good conductors of heat and electricity
- ductile
- malleable
Ductile
Metals that can be drawn into wires
Malleable
Metals that can be hammered into different shapes
Non-metals
- dull appearance
- poor conductors of heat and electricity
- brittle
Compound
- Pure substance made of two or more elements
- Combined in fixed proportion
- Has more than one atom
- can only be broken down by chemical means
- may contain ions or molecules
Ions
- Particle of an atom carrying a charge
- Axions or Cations
- Formed when metals loses electrons and non-metals gain those electrons
Mixture
- contains two or more substances (could be molecules or compounds)
- can be separated by physical means
Physical Separtion
- the separation of a mixture using a change of energy
- ie: sea water has NaCl. By applying heat to the waters boiling point, the water separates from the salt by evaporating and the heavier NaCl remains at the bottom
Physical Change
- A substance may change shapes or state, but remains the same substance.
- ie: when heated to boiling point, water may become steam; however, it is still water
Chemical Change
- Involves changing one or more substances into different
- compounds might decompose into its elements, or into new compounds
Decompose
Compound breaking apart into its elements
Composition of Substances
Composed of Atoms, ions, and Molecules
Atom
- smallest part of an element that behaves like a bulk sample of said element
- 10 to the -10 in diameter
Molecule
- A group of atoms bound together so they behave as a single particle
- The smallest particle of a compound that behaves like a bulk sample of said compound
- a few elements existing as individual atoms (such as helium, neon, argon
- Can be diatomic or polyatomic
- Compounds formed between atoms of different non-metals (ie: Carbon dioxide- CO2; aspirin - C9H8HO4)