H.Chemistry Final Flashcards
SI unit of mass and it’s symbol.
Kilograms
Kg
SI unit of length and it’s symbol.
Meter
m
SI unit of time and it’s symbol.
Seconds
s
SI unit of temperature and it’s symbol.
Kelvin
K
SI unit of volume and it’s symbol.
Cubic meter
m^3
SI unit of density and it’s symbol.
Kilogram per cubic meter
Kg/m^3
Which of the six SI units are derived units?
Volume and density
Equation for converting Celsius to kelvin
K=t(c)+273.15
Equation for converting Kelvin to Celsius
C=t(k)-273.15
Tells how close the individual measurements are to each other.
Precision
Describes how close the measurement is to the accepted value
Accuracy
Proposed explanation for an observation
Hypothesis
Tested explanation for a broad set of observations.
Theory
Standard use for comparison
Control
Variable that is manipulated
Independent variable
Variable that is observed, responds to independent variable.
Dependent variable
Equation of the error and percent error
Error=experimental-accepted
Percent error= error/accepted x 100
Ability of a substance to undergo a specific chemical change. Examples.
Chemical property
- decomposition
- rust
- acid
- water
- combustion
Quality of a substance that can be observed without changing the substances composition.Example.
Physical property
- hardness
- color
- conductivity
- malleability
Change that produces matter with a different result than the original matter. Examples.
Chemical change
- color change
- light or energy involved
Properties of a material change, but the composition of the material doesn’t.
Physical change
- dissolving
- changes in state
Depends of the type in a sample, NOT the amount of matter.
Intensive property
- density
- absorbency
Dependent upon the amount of matter in a sample.examples.
Extensive property
- mass
- volume
- length
The shape of a solid is…
Definite
Those a solid have attractive forces?
Yes
The shape of a liquid is….
Indefinite
The volume of a solid is…
definite
The volume of a liquid is…
Definite
Do liquids have attractive forces?
Yes
The shape of a gas is…
Indefinite
The volume of a gas is…
Indefinite
Do gases have attractive forces
No
List the four postulates of Dalton’s atomic theory.
- All elements are composed of tiny indivisible particles called atoms.
- Atoms of the same element are identical. The atoms of one element are different from those of any other element.
- Atoms combine in simple whole # ratios.
- In a reaction, atoms are rearranged but they are never changed into atoms of another element as a result of a chemical reaction.
Describe rutherford’s experiment
- concluded there must be a particle in the nucleus carrying a charge equal but opposite of the electron that was called a proton.
- concluded that the atoms was mostly empty space.
Location, charge, and mass in amu of the neutron.
Nucleus , 0, 1
Location, charge, and mass in amu of the electron.
Outside, negative, 1/1840
Location, charge, and mass in amu of the proton.
Nucleus, positive, 1
How do u get the mass number?
Protons+neutrons
Which particles have the same number unless it is an isotope?
Atomic number
Protons
Electrons
Who do you find the amount of neutrons?
Mass number-protons
Atoms of the same element with the same number of protons, but different mass numbers and different numbers of neutrons
Isotopes
Equation to find the average atomic mass
(Mass first isotope) x % abundance/100
+
(Mass second isotope) x %abundance/100
Alpha decay equation
4
He
2
Beta decay equation
0
e
-1
Gamma decay equation
0
Y
0
The number of wave cycles that pass a given point per unit of time. Unit.
Frequency
Hz, 1/s, s-1
Distance between crests. Unit.
Wavelength
m
Minimum amount of energy that can be gained or lost by an atom.
Quanta
Three-dimensional region around the nucleus in which an electron moves and is found 90% of the time.
Orbital
What happens when electrons jump to higher energy levels?
Atom absorbs energy
What happens when electrons fall from higher energy levels to lower energy levels?
Atoms releases energy
Speed of light equation.
C=hv
Photon energy equation
E=hv
Published periodic table, organized elements with similar chemical and physical properties and increasing atomic mass.
Mendeleev
Arranged periodic table in order of increasing atomic number.
Moseley
Column on the periodic table
Group
Across/rows on the periodic table
Period
Estimated as half the distance between the nuclei of 2 like atoms of the same element when atoms are joined.
Atomic radii
Energy needed to remove an electron from an atom.
Ionizaton energy
Ability of an Atom of an element to attract electrons when the Atom is In a compound.
Electronegativity
Total charge of all protons in the nucleus
Nuclear charge
Energy levels in an atom
Shells
Inner level electrons that interfere or shield the valence electrons from the nucleus.
Shielding
What particle determines most of the properties of elements?
Electrons
What happens to electrons in an ionic compound?
They are transferred
What happens to electrons in a covalent bon?d
They are shared
Atoms will gain or lose electrons to acquire a full set of 8 valence electrons.
Octet rule
What does VSEPR mean?
Valence shell electron pair repulsion
Molecule has H-F, H-O, or H-N
Hydrogen bonding
Caused by momentary dipoles of constantly moving electrons between nonpolar molecules
Dispersion forces
Dependent on the number of electrons, more electrons stronger forces
Dipole-dipole forces
How can you identify a polar molecule?
- Have to have at least one polar bond
- polar bonds can’t cancel
Five reaction types
Synthesis Combustion Decomposition Single replacement double replacement
What happens to the nuclear charge when it moves across the periodic table?
Increases
What happens to the nuclear charge when it moves down the periodic table?
Increases but cancels out
What happens to shells and shielding when it moves across the periodic table?
It’s constant
What happens to the shells and shielding when it moves down the periodic table?
Increases
What happens to the atomic radius when it moves across the periodic table?
Decreases
What happens to the atomic radius when it moves down the periodic table?
Increases
What happens to the ionic size when it moves across the periodic table?
Decrease
What happens to the ionic size when it moves down the periodic table?
Increases
What happens to the ionization energy when it moves across the periodic table?
Increases
What happens to the ionization energy when it moves down the periodic table?
Decreases
What happens to the electronegativity when it moves across the periodic table?
Increases
What happens to the electronegativity when it moves down the periodic table?
Decreases
What is the relationship between bond strength and bond length?
They are inversely proportional
What is a precipitate?
Formation of a solid in a chemical reaction