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