Unit 5--Spring Flashcards
To increase comprehension of the subject through repetition of vocabulary and core concepts.
What are the two parts found in the nucleus of an atom?
proton and neutron
Where are electrons found in an atom?
electron cloud
proton
positive charged particle; found in nucleus
neutron
neutral particle; found in nucleus
electron
negatively charged particle; found outside nucleus in electron cloud
nucleus
center of atom; contains protons and neutrons
quarks
particles that make up protons and neutrons
mass number
number of protons and neutrons in an element
atomic number
number of protons in an element
number of neutrons in an element is found by
subtracting atomic number from mass number
isotope
an element with same number of protons and differing number of neutrons
chemical symbol
shorthand letter representation for each element
horizontal rows
periods
vertical columns
groups
chart where elements are listed by increasing atomic number
periodic table of elements
Periods
increasing atomic number; similar chemical and physical properties in each period
groups
similar chemical properties in each group
metals
located on the left of periodic table; shiny, good conductors
non-metals
located on the right side of periodic table; mostly gases
metalloids
possess characteristics of both metals and non-metals; located in middle and right side of periodic table
synthetic
man-made elements; do not exist in nature
organic
elements that are found in nature; composed primarily of carbon, hydrogen and oxygen
valence electrons
electrons located in the outermost electron shell; where bonding occurs; 8 is the maximum number of electrons in this level; have the most energy
Mendeleev
first scientist to organize elements into chart; by atomic mass
Moseley
re-organized periodic chart by atomic number
compounds
2 or more elements chemically bonded together
chemical bond
force that holds atoms together; done by gaining, losing or sharing valence electrons
electrons closest to nucleus have
the least amount of energy; only 2 can be in this energy level
energy level
amount of energy an electron can have
eight electrons
fill the second energy level; have more energy than first energy level with 2 electrons
number of valence electrons
tells how many bonds an atom can form
valence electrons in groups
have the same number of valence electrons
electron dot diagram
model showing valence electrons around an element’s chemical symbol
stable atoms
have eight valence electrons (4 pairs); atoms want to have 8 valence electrons and form bonds to get it
unstable atoms
have unpaired electrons; number of unpaired electrons equals number of bonds atom can form
noble gases
group 18; have 8 valence electrons
ion
atom that has more electrons than protons OR more protons then electrons
positive ion
loses electron(s)
negative ion
gains electron(s)
ionic bond
forms between metals and nonmetals
covalent bond
equal sharing of electrons
metallic bond
bond between metals; electrons “pool” or float in a sea around positive nucleuses
polar molecule
slightly negative or positive end to the molecule; example water
electron dot diagram
shows unpaired valence electrons(outer shell electrons); electrons available to bond
Which particle in an atom is involved in chemical bonding?
electron
Single covalent bonds
one pair of valence electrons
double covalent bonds
two pair of valence electrons
triple covalent bonds
involve three pairs of valence electrons and are the strongest covalent bond
Which group of elements is the most stable?
Noble gases; group 18