Related Clues:

• Electron's home
• What the Bohr model depicts
• Quark's locale
• Molecular building block
• First half of encyclopedia that's been split
• Half the alphabet is minute
• It's elementary
• Particle categorically stopping short of nitrogen?
• Morsel for a cat
• Basic thing categorically followed by no?
• Very little to fill in the morning hours
• One driving test reversing a bit
• A boy, very small
• Scrap for a cat
• One can tell automatically oxygen involved - it's basic