Matter and Energy
chemical change
A change that produces matter with a different composition than the original matter
physical property (definition)
A characteristic of a pure substance that can be observed without changing it into another substance
substance
A single kind of matter that is pure and has a specific set of properties - either an element or compound - pure in nature
precipitate
A solid that forms and settles out of a liquid mixture
conservation of energy
Energy cannot be created or destroyed; it may be transformed from one form into another, but the total amount of energy never changes
gases
Have no definite shape or volume; Take the shape and volume of its container; particles far apart; High kinetic energy; no cohesive forces.
Energy
The capacity to do work or cause change or produce heat
physical change
a change in a substance that does not involve a change in the identity (or composition) of the substance
chemical property (definition)
a characteristic of a substance that when observed a new substance is formed
product
a chemical substance formed as a result of a chemical reaction
reactant
a chemical substance that is present at the start of a chemical reaction
solution
a homogeneous mixture of two or more substances
extensive properties
a physical property, such as mass, length, and volume, that is dependent upon the amount of substance present
Bose/Einstein condensate
a state of matter that can form near absolute zero when the atoms slow their motion enough to merge into a single "super-atom", all of the particles are in the same quantum (energy) state; acheived by using lasers slow down particles
compounds
a substance made up of atoms of two or more different elements chemically combined in fixed proportions
units of energy?
calories or joules
exothermic
chemical reaction in which energy is primarily given off in the form of heat
4 evidences of a chemical reaction
color change, heat change, precipitate formation, gas production
physical property (examples)
color, hardness, density, m.p., b.p., etc...
compound vs homogeneous mixture
compound broken down by chemical means - all samples are the same - pure : homogeneous mixture broken down by physical means
compound vs. element
compound can be broken down into simpler things; elements cannot; properties of the compound are different than the elements in it
heterogeneous
mixture that is not uniform throughout
homogeneous
mixture that is uniform throughout
kinetic energy (examples)
motion of particles of matter, any moving object, heat, light, etc
liquids
no fixed shape but a fixed volume; particles close together but can flow past one another; moderate kinetic energy; moderate cohesive forces
intensive properties
properties that do not depend on the amount of matter present - does not change no matter the amount of the sample - those which identify the substance
chemical property (examples)
reactivity, flammability, toxicity, oxidation states, etc...
4 ways of separating mixtures
settling, decanting, filtering, distillation
elements
simple substances that cannot be broken down into simpler substances; a pure substance that is made up of only one kind of atom
Matter
that which has mass and occupies space
joule
the SI unit of energy; , a unit of work equal to one newton of force applied for one meter
conservation of mass
the principle stating that matter is not created or destroyed during a chemical reaction
chemical reaction
the process by which one or more substances change to produce one or more different substances
states of matter
The physical forms of matter, which include solid, liquid, gas and plasma.
endothermic
describes a reaction that absorbs energy from the surroundings
separating mixtures
differences in physical properties can be used to separate mixtures
products have more energy than reactants?
endothermic
surrounding near this reaction cools off
endothermic
exothermic
energy hill decreases as reaction procedes
endothermic
energy hill increases as reaction procedes
kinetic energy (definition)
energy of motion
potential energy (definition)
energy of position (stored)
reactants have more energy than the products?
exothermic
surroundings near this reaction heats up
exothermic
potential energy (examples)
gravitational potential, chemical potential energy, electrical potential energy
solids
have a definite size and shape; particles are packed together tightly and are in a regular pattern, low kinetic energy, strong cohesive forces
ways of breaking down compounds
heat or electrolysis or chemical action
plasmas
highly ionized, electrically conducting gases; very high kinetic energy; most common state of matter; found in interior of stars; produces light
types of energy
kinetic and potential
mixture
two or more substances mixed together (not in fixed proportions and not with chemical bonding)
calorie
unit of heat defined as the quantity of heat required to raise the temperature of 1 gram of water by 1 degree Celsius
how are matter and energy related?
you can't have one without the other both bring about changes int he other a small amount of mass can be converted into a huge energy yield (E=mc²)
