Periodic Pairs
Element Matching Game
iPhone
Match by Symbol
Match by Atomic Number
Match by Atomic Weight
Match by Emission Spectra
Portrait
Landscape
iPad
Match by Symbol
Match by Atomic Number
Match by Atomic Weight
Match by Emission Spectra
Landscape
Split Screen
Split Screen Compact
macOS
Match by Symbol
Match by Atomic Number
Match by Atomic Weight
Match by Emission Spectra
