Test #1 Flashcards
Chemistry is the study of what
COMPOSITION of substances, and the CHANGES they undergo
 A theory is what
EXPLANATION of us, phenomenon or event, based on a lot of experimental evidence
What is a scientific law?
STATEMENT (not explanation) based on a lot of experimental evidence 
What are the two types of matter?
Pure substance or mixture. Pure substance is elements or compound mixture is homogeneous solution or heterogeneous.
What is aMorphous?
Without shape or form
What is crystalline?
Particles that form regular repeating three dimensional geometric patterns
What is a compound?
A pure substance, composed of two or more elements CHEMICALLY combined in a DEFINITE proportion
Another name for a homogeneous mixture is a what
Solution
What’s the difference between homogeneous and heterogeneous?
Homogeneous is no visible boundary, components, mixed as individual atoms, ions, or molecules. One phase.
 Heterogeneous is visible boundaries between components and 2+ phases. Components, retain physical properties.
What is a phase
Homogeneous part of the system. Separated from other parts by physical boundaries.
What is a system?
Body of matter under consideration
What is a physical property?
Properties of a substance shows by itself without interacting with another substance. Color, melting point, boiling point, density.
What are chemical properties?
Properties of a substance shows as it interacts with, or transforms into other substances. Flammability, corrosiveness.
What are the separation techniques?
FECCD
Filtration based on particle size
Extraction differ solubility in different solvents
Crystallization different soluability
Chromatography solubility in solvent vs stationary phase
Distalization different volatility
What’s the most abundant element on earth?
Oxygen
What is sublimation
To change directly from a solid to a gas
What are the properties of metals?
Shiny, ductile (stretch into wire)
Malleable hammer into sheet
 Good conductors
High melting points
What special solution can metals combine with a nonmetal to form?
Alloy. Bronze brass stainless steel.
What are characteristics of nonmetals?
Doll in appearance
Low melting point
Poor conductor
Brittle
Oxygen, hydrogen, Karen
What are metalloids also known as
Semiconductors
Periodic means what?
Repeating, according to a pattern
Elements with similar properties are found where on the periodic table
Vertical, columns called groups or families
What properties do alkali metals have?
Extremely reactive metals found in the first column
What properties do alkaline metals have
Reactive metals found in second column
What groups are transition elements found in?
Three through 12
What properties do halogens have, and where they found?
Very reactive nonmetals found in group 17
What properties do noble gases have?
Highly unreactive nonmetals found in the final column through 18
All of the elements left to the stairstep are what?
Metals. Except for hydrogen.
Where are the representative elements?
Group one and two, group 13 through 18
What are diatomic molecules and which ones are they?
Molecules containing two atoms of the same element bonded together
Have no fear of ice cold beer
Hydrogen
Nitrogen
Fluorine
Oxygen
Iodine
Chlorine
Bromine
What are ionic compounds?
Formed from ions that are either positive or negative
What’s the name of the two periods at the bottom of the periodic table?
Inner transition elements. Lanthanide, and actinide
What’s the difference between a compound and a mixture?
A compound is combined, chemically, distinct substance, combined in a definite ratio
A mixture is combine, physically, individual components retain their properties, variable in composition
What is an ion?
Positive or negatively charged atom or group of atoms
The smallest piece of an ionic compound capable of independent existence is called what
Formula unit(not molecule)
CaCl2 is an example of what
Chemical formula. Used to represent the composition of chemical compounds.
What is the law of definite composition?
A compound containing 2+ elements chemically combine in a definite proportion by mass
What is the law of multiple proportions?
Atoms of two+ elements may combine in a different ratio to produce more than one compound
Who wrote the atomic theory?
Dalton
What did Dalton’s atomic theory contain?
Elements composed of INDIVISABLE atoms
 Atoms of the same element are chemically alike/diff ones diff
Atoms combine in whole number ratios to form compounds
Atoms of same two elements can combine in different ways to form different compounds
Regarding charge force equals what?
How far away the Chargers are from each other and the amount of charge
Faraday discovered what?
Some substances conduct electricity when dissolved in water, and some compounds decomposed into CHARGED PARTICLES CALLED IONS
Arrhenius contributed what
Compounds can conduct when melted because they separate into ions
Anions equal negative ions
Cations equal positive ions
JJ Thompson discovered what?
The electron using experiments involving cathode rays
Atoms, form ions, through loss or gain of what
Electrons
What are the two observation from Rutherford’s gold foil experiment?
Most of the alpha particles went straight through the gold foil. He concluded most of the atom is empty. Space
Very few alpha particles bounce off the gold foil. He concluded the alpha particles hit something. :
Small
Positive
Massive
He discovered the nucleus
How did the nuclear model of the atom change from Dalton or Thompson’s model
Most of the mass is in the nucleus
Most of the atom is empty. Space.
Atoms are neutral. Equal protons, and electrons.
What is the atomic number?
The number of protons in the nucleus
What is an isotope
Atoms of the same element with different number of neutrons neutrons
What is the mass number?
Protons and neutrons added
Is mass number on the periodic table?
No
Lithium -6 means what
Hyphen Notation.  After the hyphen is the mass number.
What is nuclear (or isotope) notation?
6
Li
3
Top number is mass number.
Bottom number is atomic number.
Is atomic mass the same as average atomic mass?
Yes
All elements are compared to what regarding mass?
Carbon 12 isotope
What is electromagnetic radiation?
Any form of energy that travels through space as a wave. Radio waves, microwaves, infrared, radiation, UV.
What is a wave length?
Distance from crest of one wave to crest of the consecutive wave
What is a frequency?
The number of waves that pass a particular point each second
What is speed? Of waves?
Distance a wave moves in a certain period of time
Regarding the debate of whether light was a wave who helped settle this
Einstein. Explain a phenomenon known as photo electric effect.
What are photons?
The way light transfers, its energy in bundles or packets
Scientist describe light as what
Both particle and wave. Dual nature of light.
What is Thompson’s plum pudding model
Electrons exist throughout the atom, along with positive protons like dried fruit in a pudding
What is Bohrs planetary model
Electrons revolving around nucleus, like planets orbit.
He believed each orbit corresponded to energy transition
When atoms absorb energy electrons move to higher energy level. Excited state.
Lowest energy state for a particular electron is known as GROUND state
When electrons return to ground state, they give us a characteristic color
What is the wave model?
Current model of the atom. deBroglie Schrödinger
 Treat electrons as Waves and particles
Schroedinger calculated probability/chance of finding electron in certain region
And wave mechanics what is orbital
Most probable location for an electron in electron cloud
In wave mechanics, what is principal energy level
Most probable distance of an electron from nucleus
What is a sub level?
Division of principal energy level SPDF
What is principal quantum number?
Main energy level designation/DISTANCE FROM NUCLEUS
What is angular momentum quantum number?
Energy sublevel electron occupies:
Number of sub levels equals principal quantum number
Energy level one has one sub level energy level two has to sub levels…
SPDF
What is magnetic quantum number?
ORIENTATION of sub level in space
S orbital has one position, P orbital has three positions…
Spin quantum number. What is it?
Spin is defined as clockwise or counterclockwise
What is that Aufbau principal?
Electrons fill orbitals of lowest energy first
What is the pauli exclusion principle?
 I am an orbital can only hold two electrons and they must be, opposite spin
What is Hunds rule
When electrons fill orbitals of equal energy, one electron will occupy each orbital before they pair up
How do we find the total number of orbitals?
Square, the principal quantum number/energy level
1= 1
2= 4
3=9
4=16
How do we find out the total number of electrons in a
principal quantum number/energy level?
2n squared
n= principal, quantum number/energy level
1=2 e-
2= 8
3=18
4= 32
How do we determine valence electrons?
Use the group number OLD SYSTEM
This doesn’t work for transition metals
What a maple leaf be homogeneous?
No
Which of the following is a pure substance? Air, orange juice, nitrogen, soil.
Nitrogen
Ordinary table salt is composed of two elements, sodium and chlorine. Sodium is a highly reactive metal even reacting violently with water. Chlorine is a toxic, pale, yellow, green gas. How do these properties of these two elements compare to the properties of a compound, sodium chloride, commonly known as table salt?
Separately, the elements of sodium and chlorine are highly reactive as they easily lose electrons, when in contact with an a another substance however, as a compound, NaCl has ions that attract each other strongly, and it’s not easily broken/reactive.
Is the following statement an observation hypothesis for experiment?
There is a direct relationship between the volume of a gas and temperature
Hypothesis
Which of the following is not a pure substance? Gold NACL, crude oil, sugar
Crude oil
How many atoms does the following have? Ca(ClO3) 2
9
Which of the following is not one of the diatomic elements
Hydrogen carbon, nitrogen, oxygen
Carbon
How is an atom different from a molecule?
A molecule is the smallest component of a compound. However, an atom is the smallest component of an element capable of independent existence.
Is air a pure substance or a mixture?
Mixture
Helium is what state at room temperature?
Gas
Go thru through photos of chapter 10 WS  for more study prompts
How do I write the old system group numbers for valence electrons?
Number the representative elements
1,2 then skip the transition elements
and write 3-8 in the right representative
Then transition elements write 3-7
Ands the next three groups write 8
Then 1, 2
Remember that in figuring out principal quantum number or main energy level for transition metals, you would use the typical period number -1
What do valence electrons do in a chemical change?
Gain lose or share electrons
Atoms of the same element with different number of neutrons are called what?
Isotopes
How do how do I figure nuclear notation?
And then I write in the answer I’m just doing microphone