Chapter 1 Flashcards
______ properties ______ depend on sample
Intensive; don’t
_______ Properties ________ depend on the sample
Extensive; do
Summarize past experiments; predict future ones
Law
Speculation, proposed reasoning based on several hypothesis
Theories
Seven fundamental units
SI Units; Mass - kg; length - m; Time - s; Temp - K; Substance - mol; volume - m^3
Constant because quantity of matter cannot change
Mass
Variable, dependent on gravity
Weight
Ratios used to express a quantity of dif units
Conversion factors
Conversion factor chosen must _______ all units except the unit in the _______
Cancel out; answer
Measure of how hot or cold an object is relative to another
Temperature
Energy that flows from object with higher temp to lower temp
Heat
T(inC) + 273.15 = __
Celsius to Kelvin
[T(inF) - 32]x5/9 = ____
Fahrenheit to Celcius
A characteristic & physical property, ratio of ______ & _______
Density;Mass/Volume
Mass, volume, energy, ______ on amount of substance
Extensive property; dependent
Density, temp, _______ on amount of substance
Intensive property; does not
How close measurements in series are to eachother
Precision
How close each measurement is to the actual value
Accuracy
Either ALL higher OR lower than actual value
Systematic
Higher AND lower than actual value
Random
Peta (P)
10^15
Tera (T)
10^12
Giga(G)
10^9
Mega(M)
10^6
Kilo(k)
10^3
Hecto(h)
10^2
Deka(da)
10^1
Deci(d)
10^-1
Centi(c)
10^-2 (0.01)
Milli(m)
10^-3
Micro(u)
10^-6
Nano(n)
10^-9
Pico(p)
10^-12
Femto(f)
10^-15
Pure substance
- Made up of only one distinct chemical component
- composition is homogenous and uniform throughout.
Mixture
- Composed of two or more chemical components
- Proportions can vary from one sample to another
Element
- Substance that cannot be chemically broken down into simpler substances
- Only one atom “type” is present
Compound
Substance composed of two or more elements in fixed definitive proportions
Law of definite/constant composition
Elemental composition of a compound is always the same
Compounds can be represented by 3 formulas. What are they?
Molecular, Empirical, Structural
Empirical Formula
Relative number of atoms of each element in a compound
Simplest whole number (ratio) representation of the type & number of elements in the molecule
Molecular Formula
Gives the actual number of atoms of each element in a molecule of a compound
Because ________ are held together by defined chemical bonds, they are referenced using __________
Molecular compounds;molecular formula
Because ________ are not held together by defined chemical bonds, they are referenced using ________
Ionic compounds; empirical formula
Cations
Positive ions; number of electrons decreases
Anions
Negative ions; number of electrons increases
__________ atoms lose electrons and become ___________
Metal; cations
____________ gain electrons and become ________
Nonmetals; anions
Homogeneous mixture
Mixture made of multiple compounds, appears as one substance
Uniform compositions, mix uniformly
Each component retains some or all of its own unique identity/properties
Ex. Sea water, tea
Heterogenous Mixture
The composition varies from one part of the mixture to the other
Portions have different composition and properties
Ex. Concrete
Physical Mixtures can/can’t be separated by physical means
Can be separated by physical means
Chemically reacted compounds can/can’t be separated using physical means
Can’t be separated by way of physical means
Filtration
Separates based upon differences in particle size
Crystallization
Separates based upon differences in solubility
Distillation
Separates based upon differences in volatility
Chromatography
Separates based upon differences in solubility
Law of Conservation of Mass
Mass is neither created nor destroyed through chemical reactions
Formula for law of conservation of mass
SUM (mReactants) = SUMmProducts + SUMmexcess reactants
Law of Conservation of Mass-Energy
The amount of mass-energy must be conserved in a closed system
Law of Multiple Proportions
When two or more elements form a series of compounds, the ratios of the masses can always be reduced to a small whole number
Avogadros Hypothesis
At the same temperature and pressure, equal volumes of different gases contain the same number of particles
Cathode Rays Experiments
JJ Thomson, atom must be composed of negatively charged particles
Particles must come from something that all atoms have in common
Atoms are not indivisible as Dalton thought
Millikan Oil-Drop Experiment
X-rays used to number electrons
Determined charge of electron
1.602 x 10^-19
Combining results gave mass of electron 9.10 x 10^-28
Particles with the ______ charge repel eachother, whereas particles with _____ charges attract one another
Same;unlike
Radioactivity
The spontaneous emission of radiation by an atom
Three types of radiation
A particles, b particles, y rays, Rutherford
B rays are _______ charged (_e) and have mass, consist of ________
negatively;-1;electrons
A rays are _______ charged (_e)
Positively; +2
Electrons want to
Minimize their distance from protons; maximize separation from other negatively charged particles
Rutherford Gold Foil
Proved existence of both positive and neutrally charged particles in the nucleus
Modern atomic theory
Atoms are divisible into protons, neutrons, electrons.
All the atoms of an element contain the same number of protons and electrons
Number of protons defines the element & is called the atomic number
Atoms of the same element can have different properties
Isotopes
Atoms with identical #’s of protons and electrons, differ # of neutrons
Mass number, A
The total number of protons and neutrons in an atom
Used to differentiate between isotopes of an atomic element
Masses of atoms and percent abundances of isotopes are measured using ________ - a technique that separates particles according to their mass
Mass spectrometry
Statistical average mass
MAtomic = SUMisotopes Misotope x NAfractional
Avogadros #
6.022 x 10^23 amu
Periods
Rows of the periodic table
Groups
Columns of the period table, similar properties
Ionic Compounds
Electrostatic attraction between ions
Metal and Nonmetal
Polyatomic ions
Covalent (Molecular) Compounds
Sharing of electrons between atoms
Multiple nonmetals
Represented with molecular formula
Removing electrons results in a positively charged _______
Cation
Adding electrons results in a negatively charged ______
Anion
Metals tend to ______ e- to form ______
Lose;cations
Nonmetals tend to _____ e- to form _____
Gain, anions
Ionic Charge Trend
Group 1: +1, Group 2: +2, Group 13: +3, Group 14: +-4, Group 15: -3, Group 16: -2, Group 17: -1, Group 18: 0
H(+)
Hydrogen Ion
Li(+)
Lithium ion
Na(+)
Sodium ion
K(+)
Potassium Ion
Rb(+)
Rubidium ion
Cs(+)
Cesium ion
Fr(+)
Francium ion
Be(2+)
Beryllium ion
Mg(2+)
Magnesium ion
Ca(2+)
Calcium ion
Sr(2+)
Strontium ion
Ba(2+)
Barium ion
Ra(2+)
Radium ion
Sc(3+)
Scandium ion
V(2+)
Vanadium(II) ion
V(4+)
Vanadium(IV) ion
Cr(2+)
Chromium(II) ion
Cr(3+)
Chromium(III) ion
Mn(2+)
Manganese(II) ion
Mn(3+)
Manganese(III) ion
Fe(3+)
Iron(III) ion
