Colors Memorization List
Flame Tests, Aqueous Ions, Compounds, Indicators
Flame Test Colors
Li+
Na+
K+
Ca2+
Sr2+
Ba2+
Cu2+
Deep red (crimson)
Yellow
Violet
Orange-red
Red
Yellow-green
Blue-green
Aqueous Ion Colors
Ions of transition metals with partially-filled d orbitals are colored in solution; ions of s- and p-block elements are usually clear in
solution
Cu1+
Cu2+
Fe
Green
Blue
Yellow to red-orange (depending on anion and charge of Fe); in rare cases, can form complex ion with a deep blue
color
Fe2+
yellow-green (depending on the anion)
Fe3+
orange-red (depending on the anion)
Cr3+
Violet (Cr(NO3)3 to Green (CrCl3)
Ni2+
Green
Mn2+
Pink
MnO4−
Purple (e.g., Mn+7 in the MnO4− ion)
3+
Pb
blue-green (Pb2+ and Pb4+ are colorless)
2+
V
violet
V3+
blue-green
CrO42−
Yellow
Cr2O72−
Orange
Cu(NH3)42+
Dark Blue; produced when ammonia is added to Cu2+ solutions
2+
FeSCN
Red-brown, Wine-red to dark orange
CoCl42−
Blue (Co2+ with HCl will form a CoCl42− complex that is blue)
2+
Co
Pink
Ti(H2O)63+
Purple
Al, K, Li, Mg, Na, Ca, Ba, Sr, Zn are colorless aqueous ions and most of their solid salts are white.
Assorted Compounds
F2
Cl2
Br2
I2
S8
NO
NO2
PbI2
Metallic sulfides
Fe2O3
Metallic oxides
Pale-yellow gas
Green-yellow gas
Red-brown liquid
Dark-violet vapor & dark metallic looking solid
Yellow, odorous solid
Colorless gas; associated with reactions between metals and dilute HNO 3
Brown gas; associated with reactions between metals and concentrated HNO 3
Bright yellow precipitate
Sulfides of transition metals tend to be black
Reddish brown (rust)
Oxides of colored transition metal ions tend to be colored
Acid-Base Indicators
Phenolphthalein
Red Litmus (paper)
Blue Litmus (paper)
Colorless (pH<7) to Pink (pH>8 ; when OH- is present)
Turns purple-ish blue in alkaline solution
Turns pink-ish red in acidic solution