atoms can be considered roughly ________
the protons and neutrons are tightly clustered in the middle, the ________
outside nucleus, ________, it is huge relative to the ________ (4 orders of magnitude bigger!)
spherical, nucleus, electron cloud, nucleus
the nucleus is approximately 0.000001% of the atom's volume BUT its _____% of the atoms' mass
mass--> _________ volume --> ________
the electron cloud is essentially ________, while providing all the ________
99.95, nucleus, electron cloud, massless, volume
atoms are electrically ________
neutral
the defining feature of an element is the number of ________ it has
"what makes a carbon carbon is that is has 6 ________ and not 7 - its like a social security number
protons, protons
ATOMIC NUMBER:
the number of ________ in an element is called the atomic number (z_
Neon: 10 ________ --> ??Ne
protons, protons, element, atomic #
MASS NUMBER:
most elements have masses greater than their atomic number because most have ________.
neutrons
mass number: number of ________ + number of ________
symbol: __
Neon: 10 ________ + 10 ________--> ___ : 20
�?Ne
protons, neutrons, A, protons, neutrons, A
amu =
it is 1/12 of the mass of a ?? atom
? C
atomic mass unit
different atoms of the same element can have different numbers of neutrons and these are called ________.
isotopes
some ________ occur more abundantly in nature than others
(percentages of each one certain kind is more than another)
isotopes
ATOMIC WEIGHT
the statistical ________ of the ________ of the isotopes of an element
Br atomic weight: 79.904 amu (this will always be listed on ________)
average, masses, periodic table
when atoms of two or more elements combine, they form a ________
which one is a compound? N? or H?O
compound, H?O
the ________ is the list of all the elements present in a compound, using subscripts to reflect the # of Br of each element
ethanol ---> ________
octane ---> ________
vinegar --> ________
chemical formula, C?H?O, C?H??, C?H?O?
MOLECULES VS. IONS:
the chemical formula for a molecule: ________
the sum of the atomic weights for all the atoms in a molecular formula is the ________.
methanol: CH?O
C 12.011 x 1 = 12. 011 ___
H 1.0079 x 4 = 4.0316 ___
O 15.9994 x 1 = 15.9994 ___
+____
the molecular formula, molecular weight, amu, amu, amu, amu