Studied by 0 people
What are the three main states of matter?
Solid, liquid, gas
What determines the state of matter of a substance?
The arrangement of the molecules and how they behave
What is a molecule?
A group of atoms of the same element bonded together
What is an atom?
A small building block or unit of matter
What is an element?
A substance whose atoms have the same number of protons
What is a compound?
Combination of two or more elements
What is condensation?
The opposite of vaporization. It occurs when gas turns to liquid.
What is sublimation?
When a solid becomes a gas, without ever becoming a liquid.
What is an example of sublimation?
Dry ice
What is deposition?
When a gas/vapor changes into a solid
What is an example of deposition?
Frost on a cold winter morning or snow forming inside clouds
What is matter?
Anything that has mass and takes up space
What are the two categories for all properties of matter?
Physical and chemical
What is density?
Ratio of mass and volume
What is volume?
The amount of space something occupies
Into what two categories are physical properties divided?
Intensive and extensive properties
What is the difference between intensive and extensive properties?
Extensive properties depend on the amount of matter being measured, intensive properties don’t
Which properties can be added together: intensive or extensive?
Extensive
Are size, length, volume, width, mass and weight examples of intensive or extensive properties?
Extensive
Are color, odor, temperature, boiling point, density and state of mater intensive or extensive properties?
Intensive
What distinguishes chemical properties?
They are characteristics that can only be observed in a chemical reaction
What are some chemical properties?
Reactivity, toxicity, flammability, and combustibility
What is reactivity?
The likelihood of a substance to undergo a chemical reaction
What are the two classifications of changes that matter experiences?
Physical and chemical
Is burning a log into a pile of ashes a physical or chemical change?
Chemical
What is an exothermic reaction?
A physical or chemical reaction that releases heat and energy
What is an endothermic reaction?
A physical or chemical reaction that absorbs heat and energy
Is making ice cubes an exothermic or endothermic reaction?
Exothermic
What is matter made up of?
Atoms
What are atoms?
The smallest units of matter that have the properties of a chemical element
What are atoms made up of?
Subatomic particles
What are the 3 subatomic particles?
Electrons, protons, and neutrons
Which subatomic particles are located in the nucleus of an atom?
Protons and neutrons
What charge does the nucleus have?
Positive
Where are electrons located?
In “clouds” at certain distances from the nucleus
What are the smallest particles?
Leptons, muons, tau particles and quarks
How are atoms usually classified?
Elements
What is a pure substance?
One made up of only one type of atom or one type of molecule
What is a compound?
A molecule that contains at least two different elements (or atoms) that are chemically combined in a fixed ratio
What is a chemical substance?
Something that can’t be separated into its components by physical methods
What does it mean to say that a compound is reacted chemically?
That each of its individual parts no longer retain their own properties
What is the difference between a compound and a mixture?
A mixture can be separated into its original parts, but a compound cannot.
What are the two types of mixtures?
Heterogenous and homogenous
Which mixtures cannot be separated by physical means: heterogenous or homogenous?
Homogenous
Is pizza a heterogenous or homogenous mixture?
Heterogenous
Is milk a heterogenous or homogenous mixture?
Homogenous
What are the 5 physical methods used to separate a mixture?
Filtration, extraction, evaporation, distillation, and chromatography
What is an insoluble solid?
One that does not dissolve
What is chromatography?
A separation process that requires two different phases of matter
What is chromatography used for?
To separate two solids that are mixed to create the same liquid
What is used to separate an insoluble solid?
Filtration
What is used to separate a soluble liquid?
Evaporation
What is extraction?
Isolating one compound from another
What is distillation?
Purifying a liquid by the process of heating and cooling.
When is distillation useful?
To separate two liquids that have different boiling points by heating them to evaporate one of them and then cooling it to condense it while the other remains a liquid
Who was the first scientist to develop an atomic theory based on scientific observation?
John Dalton
Who is the father of atomic theory?
John Dalton
When was the theory of the atom first proposed?
1803
What did John Dalton believe?
All matter is made up of atoms
Atoms cannot be broken down further
Atoms within an element are the same
What is the law of conservation of mass?
Atoms are rearranged during a chemical reaction, but are not lost
What is the law of multiple proportions?
The ratio of the number of atoms to one another is a whole number
What was John Dalton wrong about?
Atoms actually can be broken down further, into subatomic particles.
Who discovered the electron?
J.J. Thomson
How did Thomson prove that electrons exist?
He used electromagnetic radiation theory to build a cathode ray tube
What is a cathode ray tube?
A glass cylinder in which most of the air has been removed. Inside the tube are two electrodes, a cathode, and an anode
What is a cathode?
A negatively charged electrode
What is an anode?
A positively charged electrode
How does a cathode ray tube work?
When a high voltage is applied between the electrodes, a beam of electrons travels from the anode to the cathode. This allows you to determine the ratio of electric charge to the mass of a single electron
What did Ernest Rutherford discover?
Atoms are made up of mostly empty space
Atoms have a positively charged center
Who named the center of the atom?
Ernest Rutherford
Who discovered the size of the charge on an electron?
R.A. Millikan
What did R.A. Millikan determine?
The mass of an electron
Who discovered the neutron?
James Chadwick
When was the neutron discovered?
1932
What is a wave?
A vibrating disturbance through which energy is transmitted
How are waves described?
By their height and length
What is a waves amplitude?
The vertical distance from the midpoint of the wave
What is the frequency of a wave?
The number of waves that pass through one specific point
What do you call the tops and bottoms of waves?
The crests and troughs
What is the electromagnetic spectrum?
The collection of all types of electromagnetic radiation
How many parts are there to the electromagnetic spectrum?
Seven
What are the parts of the EM spectrum?
(Roger makes instruments: violins, ukuleles, xylophones and guitars)
Radio, microwaves, infrared, visible, UV, X-rays, Gamma Rays
What is the only part of the EM spectrum that humans can see?
The visible spectrum
What color has the shortest wavelength in the visible spectrum?
Violet
What color has the longest wavelength in the visible spectrum?
Red
What part of the EM spectrum has the longest wavelength?
Radio waves
What part of the EM spectrum has the shortest wavelength?
Gamma rays
Who discovered that electrons can also act like particles?
Max Planck
What are quanta?
The small packages in which EM radiation is emitted
What is the smallest quantity of energy that can be emitted or absorbed in the form of EM energy?
A quantum
What does Planck’s constant relate?
The energy in 1 quantum of EM radiation to the frequency of that radiation
What is quantum theory?
The study of matter and energy on the atomic and subatomic levels
According to quantum theory, in what size is energy always emitted?
Whole-number multiples
What effect did Einstein discover using Planck’s theory?
The photoelectric effect
What is the photoelectric effect?
Brighter light means more electrons are being ejected
What theory did Einstein develop?
The general theory of relativity
What is the general theory of relativity?
The current theory of gravitation in modern physics
What did Einstein call the beam of light that could eject an electron?
A photon
What is a photon?
A particle of light
What is the smallest unit of energy?
Photons
Note
Flashcard