ch3 Flashcards
Electron relative mass
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What is proton number?
What are the other terms used interchangeably with it?
The number of protons in an element/compound
other terms
atomic number
Atomic number: Number of protons in an element/compound
Atomic Mass (Ar): Number of protons/electrons in an element
Molecular Mass (Mr): Number of protons/electrons in a compound/mixture
p.s. no such thing as molecular number
Nucleon number
Terms used interchangeably with it
Total number of protons and neutrons in an atom
Ar/Atomic Mass/Relative Molecular Mass
Octet configuration
8 valence electrons
alt. answer
8 electrons in valence shell
Duplet configuration
2 electrons in valence shell
-ide
means…?
ide - no oxygen
Match following keywords w/ number
tetra
mono
4
1
Chemical bond strength of force
very strong
Silver charge
Zinc charge
Silver
Ag +
Zinc
Zn 2+
Is the metal written in the front or the back in a chemical formulae
Front
E.g. NaCl (Na aka Sodium is from grp 1 so it is a metal)
No one puts ClNa, they put NaCl as Na is the metal
Define Mr Value
average mass
(isotopes of element)
compared
1/12th mass (1 atom C-12)
Which grp an atom belongs to?
+ Which grp is noble gas?
Metallic (<= 3 Valence)
G1, 2, 3
Non-metallic (>3 valence)
G (10 + Valence e-)
Noble gas
G18
Why is noble gas stable
full valence shell, cannot react with other atoms
Octet config not accepted. Helium is a duplet config yet it is stable
Valence electrons = outermost electrons
charge of bromine
Br-
is bromine a metal
is barium a metal
is sulfur a metal
bromine: nonmetal
barium: metal
sulfur: nonmetal
check periodic table!!
define elements
pure substance, cannot broken down any simpler substances by chemical methods
when do molecules of elements form? are they still elements?
molecules of elements -> 2 or more atoms, same elements, chemically bonded together
yes, they are still elements
2 general classification of elements
metal
non metal
define compounds
- pure substances
- atoms of two/more different elements, chemically bonded
properties of compound
- properties different from constituent elements
- made of fixed ratio of atoms
- constituent elements only separated via chemical methods
how to form mixture?
2 diff. elements not chemically bonded tgt
2 diff. compounds not chemically bonded tgt
elements + compounds not chemically bonded tgt
NOT formed by chemical reactions
define mixture
different substances exsisting tgt,
not chemically bonded tgt
how does impurities affect boiling/melting pt?
- melt/boil over range of temp.
- above pure substance boiling pt.
- below pure substance melting pt.
i.e.
pure substance X 90 deg melting, 100 deg boiling becomes a wider scope.
impure substance X 70-89deg melting, 101-150deg boiling
