exam 1 Flashcards
The study of matter
Chemistry
The study of all matter
General Chemistry
The study of matter based on carbon and hydrogen containing compounds
Organic Chemistry
The study of matter important in living systems
Biochemistry
Identity and amount of matter (what is made and how much of each component)
Composition
How the parts are connected/joined
Structure
Describe the material itself without causing changes in composition
Physical Properties
Describes a material in terms of its reaction with other materials
Chemical Properties
The simplest pure substance, cannot be separated into anything smaller and unique by either physical or chemical means
Element
A pure substance, the different atoms have chemically joined to form this new material and have done so in a set ratio
Compound
Not a pure substance, the matter in them is just physically jumbled together without bonding chemically into one new material, can have variable ratios and can be separated into the individual pure substances by physical means
Mixture
Techniques which separate or breakdown a mixture into its components without resorting to chemical means or destroying the components of the mixture
Physical Means
Techniques which change the chemical composition of compounds and can decompose compounds into their constituent elements or into simpler compounds
Chemical Means
reactants–>products+heat
If the energy is released as heat, the container may feel warmer or fire may result
Exothermic Reactions
reactants+heat–>heat
If the energy is absorbed as heat, the container and its contents will feel colder (this energy goes into storage within bonds)
Endothermic Reactions
Energy sometimes necessary to get a reaction started, but not necessarily required from surroundings to continue
Activation Energy
The fundamental smallest piece of matter that retains the unique properties of only that matter
Atom
An atom that has developed charge (by losing or gaining electrons)
Ion
A grouping of chemically bonded atom; neutral in charge overall
Molecule
Two or more atoms of different elements bonded together with no overall charge
Molecule
A charged group of bonded atoms
Polyatomic Ion
Come as bonded pairs when free in nature (H, N, O, F, Cl, Br, I)
Diatomic Elements
Indicates the quantity of what precedes them
Subscripts
Represents the number of complete units of what follows them
Coefficients
Often indicates charge
Superscripts
Columns, lots of similarities in properties
Group/Family
Rows
Period
First 2, last 6 columns
Main Group Elements
Left/down of staircase
Solid at room temperature, luster, malleable and ductile, really high melting point, most conduct heat and electricity
Metals
Up/right of staircase
Usually gases or solids at room temperature, dull or chalky, brittle solids, much lower melting point, most are poor conductors
Nonmetals
Si, Ge, As, Sb, Te, Po
Metalloids/Semimetals
10 center columns
Transition Metals
1st column
Alkali metals
2nd column
Alkaline earth metals
17th column
Halogens
18th column
Noble gases
m, km, cm, mm
Length
g, kg, mg
Mass
L, mL, cm^3(cc)
Volume
about 68-72F, 22-25C
comfortable room temperature
32F, 0C
freezing point of water
212F, 100C
boiling point of water
about 98-99F, 36-37C
normal human body temperature
Not counted as sf, placeholders, only serve to locate a decimal, to show small magnitudes
0.00124, 0.5, 0.0346
Leading zeros
Always counted as sf, part of the measurement or calculated value
105 in 120.41 cm 6.0304 cm
Captive Zeros
Sometimes as sf, may only be locating a decimal point or may be the final estimated digit and significant
- to the right of a decimal point>significant
- at the end of a whole number>not significant
Trailing Zeros
The answer must not contain any decimal places beyond the smallest place value common to all of the numbers
Addition & Subtraction
The answer must not contain any sf than the least number of sf in the numbers used in the calculation
Multiplication & Division
Mass per 1 unit of volume, mass/volume
Density
Solids: g/cm^3
Liquids: g/mL
Gases: g/L
Units for density
Evidence of a chemical change?
- Color changes
- Fizz or bubbles of new gas
- Precipitate forms
- Energy absorbed or released
Two or more reactants combine to form one main product
Combination
A compound breaks down into two or more simpler compounds
Decomposition
One element replaces another element within a compound
Single Replacement
Two compounds react to produce two different compounds
Double Replacement
A specific form of double replacement:
acid+base–>a salt+water
Neutralization
A rapid chemical reaction of a substance with oxygen; burning in the presence of oxygen to give off heat, light, energy
Combustion
A compound that has only carbon and hydrogen in it
Hydrocarbon
A double replacement followed by a decomposition
Coupled Reaction
Unique ID, same as protons, found on periodic table, identifies the element
Atomic Number
p+#n in a specific, individual species
Mass Number
Atoms of the same element with different atomic masses due to different numbers of neutrons, chemical identity the same, mass slightly different
Isotopes
Describes the atomic structure for a specific atom (or ion) by giving #p, #n (within the mass number) and charge (if an ion)
Isotopic Notation
