Page 311 - (DK) The Ultimate Visual Dictionary 2nd Ed.

ATOMS AND MOLECULES
ANATOMY OF A FLUORINE-19 ATOM
Different versions (isotopes)
of each element exist, with 2p-orbital Nine negatively
the same number of protons, charged electrons
but with different numbers arranged in orbitals
of neutrons. Every atom of 1s-orbital
the element fluorine has
nine protons in its nucleus,
but the number of neutrons
can vary (from eight to
11). Fluorine-19 has
10 neutrons.
2p-orbital

2p-orbital
Atomic
Nucleus diameter
2s-orbital (about 1.2
-10
× 10 m)
Each orbital holds
up to two electrons

ANATOMY OF NUCLEUS
OF A FLUORINE-19 ATOM

First Second
electron electron
shell shell

NUCLEUS

TEN NEUTRONS NINE PROTONS
Mass of nucleus
about 19 atomic
mass units Up quark
Up quark Down quark
Gluon
Nuclear diameter
-15
Gluon Down quark (about 10 m) Down quark Up quark
NEUTRON PROTON
(NO CHARGE) (POSITIVELY CHARGED)

EXAMPLE OF COVALENT BONDING
2p-orbital
1s-orbital 1s-orbital
1s-orbital Electrons shared
in Σ-orbital
2p-orbital
Incomplete
1s-orbital of
hydrogen and 2s-orbital
2p-orbital 2p-orbital of
flourine overlap
2s-orbital 2p-orbital 2p-orbital

1. NEUTRAL HYDROGEN NEUTRAL FLUORINE 2. COVALENT BONDING: HYDROGEN
ATOM (H) ATOM (F) FLUORIDE MOLECULE (HF)
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