Periodic table, periodic trends & metals and nonmetals Flashcards
there are 118 known kinds of atoms, one kind for each element
atomic structure
charge: +1, relative mass: 1837,EQUALS TO ATOMIC NUMBER
protons
number of protons in nucleus identifies the atom EQUALS TO NUMBER OF PROTONS
Atomic number
charge: 0, relative mass: 1839, EQUALS TO MASS NUMBER/ATOMIC WEIGHT - PROTONS
neutrons
number of protons + number of neutron
mass number/atomic weight
charge: -1, relative mass: 1, EQUALS TO NUMBER OF PROTONS, IT DETERMINES THE CHEMICAL PROPERTIES OF AN ATOM
electrons
average mass of all isotopes of element
atomic mass
same element, same protons, same atomic number, diff neutrons, mass number
isotopes
= number of valence electron, vertical column of elements in the periodic table
group number
similar chemical behavior
same column
electrons in outermost of valence shell
valence electron
horizontal row of elements in the periodic table. For identification purposes, the periods are numbered sequentially with Arabic numbers, starting at the top of the periodic table.
period
In the _______ which has been in use for many years, groups are designated by using Roman numerals and the letters A and B.
first notation
In the _____ which an international scientific commission recommended several years ago, the Arabic numbers 1 through 18 are used.
second notation
are soft, shiny metals that readily react with water.
alkali metals (1A)
are also soft, shiny metals, but they are only moderately reactive toward water.
alkaline metals (2A)
are reactive elements that are gases at room temperature or become such at temperatures slightly above room temperature.
halogens (7A)
are unreactive gases that undergo few, if any, chemical reactions.
noble gases (8A)
order in the
increasing amount of chemical information that had become available.
periodic law
In 1869, these efforts culminated in the discovery of what is now called the
periodic law, proposed independently by
Dmitri Mendeleev and Julius Lothar Meyer
visual representation of the behavior described by the periodic law. a tabular arrangement of the elements in order of increasing atomic number such that elements having similar chemical properties are positioned in vertical columns.
periodic table
is the distance from the nucleus to the outer edge of the valence shell.
atomic radius
amount of energy required in order to remove electron from an atom
ionization energy
left to right, bottom to top
increasing ionization energy, decrease atomic radius
why atomic radius decrease in left to right, bottom to top
caused by increase number of proton and electron
right to left, top to bottom
increasing atomic radius, decreasing ionization energy
why increasing atomic radius in right to left, top to bottom
caused by electron shielding
why decreasing ionization energy in right to left, top to bottom
because it is far from attraction of nucleus
atomic mass = (percent/100) x given AMU, add the answers of the given, if TRACE, IT IS NOT INCLUDED
formula of AMU
an element that has the characteristic properties of luster, thermal conductivity, electrical conductivity, and malleability.
metals
With the exception of _____ all metals are solids at room temperature (258C).
mercury
an element characterized by the absence of the properties of luster, thermal conductivity, electrical conductivity, and malleability. have lower densities and lower melting points than metals.
nonmetals
The only nonmetal that is a liquid at room temperature is
bromine
properties of metals
high thermal conductivity, almost all are solids, ductile
properties of nonmetals
bad conductor of electricity, dullness, brittleness, softness
The majority of the elements are metals. Only ___elements are nonmetals
23
only nonmetals in left side
hydrogen
Most _____ are relatively common and are found in many important compounds.
nonmetals
two most abundant elements that are nonmetals?
oxygen and silicon 80.2%
all atoms in body that are nonmetals
99%
9.5%
hydrogen
65%
oxygen
18.5%
carbon
3.5%
nitrogen
2/3 of body or 9.5%
h2o
must be obtained from food sources, are called _____. Several of this are metals rather than nonmetals.
dietary minerals
