Mrk Del Qry Structure Drawing Area
S/A D/A S/D
CHO CO2H NO2 SO3H
H ?   He
He Be   B C N O F Ne
Na Mg   Al Si P S Cl Ar
K Ca Sc Ga Ge As Se Br Kr
Rb Sr Y In Sn Sb Te I Xe
Cs Ba Lu Tl Pb Bi Po At Rn
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