What did John Newlands compare the repetition of elements to?

• A musical scale

• A game of chess

• A building's structure

• A flowing river

How were electrons first imagined to move around the nucleus of an atom?

• In straight lines

• In circular paths

• Randomly

• In zig-zag patterns

How are electrons better described in modern science?

• As tiny solid balls

• As miniature planets

• As waves

• As magnetic fields

How many electrons can the 'p' orbital hold in an atom's electron shell?

• Two

• Four

• Six

• Eight

How many electrons can a d orbital hold in total?

• 2

• 6

• 10

• 14

Which orbital do electrons usually fill before the 3d orbital?

• 2p

• 3s

• 4s

• 4p

What is the name for the energy needed to remove an electron from an atom to make it a positive ion?

• Electron affinity

• Electronegativity

• Ionization energy

• Atomic energy

What is the energy called when an electron is added to an atom to make it more stable?

• Ionization energy

• Electron affinity

• Bond energy

• Activation energy