Chapter 0d Flashcards
- pure substances from which all other things are built
- cannot be broken down into simpler substances
elements
- represents the names of the elements
- consists of one to two letters and start with a capital letter
chemical symbols
- silver, shiny elements that is a liquid at room temperature
- can enter the body by vapor inhalation, contact with the skin, or ingestion of water or food contaminated with it
mercury (Hg)
organize 118 elements into groups with similar properties and placesthem in order of increasing atomic mass
periodic table
how many elements are in the periodic table
118
contains elements with similar properties in vertical columns
groups
horizontal rows of elements, counted from top to bottom of the table as 1-7
periods
written at the top of each vertical column
group numbers
use the letter A for __ __
representative elements
use the letter B for __ __
transition elements
representative elements
(Groups 1A-8A)
transition elements
(Group 3B-12B)
Group 1A
alkali metals
what are the alkali metals
- lithium (Li)
- sodium (Na)
- potassium (K)
- rubidium (Rb)
- cesium (Cs)
Group 2A
alkaline earth metals
what are the alkaline earth metals
- beryllium (Be)
- magnesium (Mg)
- calcium (Ca)
- strontium (Sr)
- barium (Ba)
- radium (Ra)
Group 7A
halogens
what are the halogens
- fluorine (F)
- chlorine (Cl)
- bromine (Br)
- iodine (I)
- located on the left of the periodic table
- shiny and ductile
- conduct heat and electricity
- solids, except for mercury
metals
- located on the right side of the periodic table
- dull, brittle, and poor conductors but often good insulators
- have low densities and melting points
nonmetals
- located along the heavy zigzag line on the periodic table
- exhibit properties of metals and nonmetals
- better conductors than nonmentals but not as good as metals
- used as semiconductors and insulators, because they can be modified to function as conductors and insulators
metalloids
how many elements are essential for the well-being and survival of the human body
20 elements
are representative minerals involve in
- formation of bones and teeth
- maintenance of heart and blood vessels, muscle contraction, nerve impulses, and acid-base balance of body fluids
- regulation of cellular metabolism
macrominerals
what are the macrominerals
- Ca
- P
- K
- Cl
- S
- Na
- Mg
smallest particle of an element that retains the characteristics of that element
atom
theory that states the properties of atoms
Dalton’s atomic theory
subatomic particles of atoms
- protons
- electrons
- neutrons
have a positive charge
protons
have a negative chargeg
electrons
have no charge
neutrons
like charges __
repel
unlike charges __
attract
realized from his experiment that cathode rays contain negatively charged particles
J.J. Thomson
model in which protons and electrons were randomly distributed in a positively charged cloud, like plums in a pudding
“plum-pudding” model
concluded that there must be a small, dense, positively charged nucleus in the atom that deflects positive particles that come close
Rutherford
what do atoms consist
- nucleus
- electrons
- located in the center of the atom
- contains protons and neutrons and represents most of the mass of an atom
nucleus
occupy a large, empty space around the nucleus
electrons
unit for atoms
atomic mass unit (amu)
mass of electron
much less than that of a proton or neutron
- equal to the number of protons in an atom
- whole number specific for each element
- same for all atoms of an element
atomic number
net charge of neutral atoms
0
neutral atoms
number of protons = number of electrons
- equal to number of protons + number of neutrns
- represents the number of particles in the nucleus
- always a whole number
- does not appear in the periodic table
mass number
- have different mass numbers
- same number of protons but different numbers of neutrons
- atoms of the same element
- can be distinguished by their atomic symbols
isotopes
- weighted average of all naturally occurring isotopes of that element
- number on the periodic table below the chemical symbol
atomic mass
consists of energy particles that move as waves of energy
electromagnetic radiation
distance between the peaks of waves
wavelength
has shorter wavelengths
high-energy radiation
has longer wavelengths
low-energy radiation
spectrum of the electromagnetic radiation emitted or absorbed by an electron during transitions between different energy levels within an atom
Atomic spectra
what are the lines in an atomic spectrum associated with
changes in energies of electrons
specific energy of electron is also known as
energy level
represents the relative overall energy of each orbital
principal quantum number n
means that the electrons can possess only certain discrete energy values; values between those quantized values are not permitted
Quantized energy
what happens when electrons fall back to a lower energy level
light is emitted
what determines the physical and chemical properties of an element
arrangement of electrons
number of sublevels in an energy level =
principal quantum number n of that energy level
what are the sublevels
s, p, d, and f
s orbitals are shown as
spheres
how many p orbitals are there
3, starting with n=2
maximum electron an orbital can hold
2
how many orbitals:
s sublevel
1
how many orbitals:
p sublevel
3
how many orbitals:
d sublevel
5
how many orbitals:
f sublevel
14
