Section 3 - Organization of the Elements

How did Dmitri Mendeleev organize elements in the late 1800s?

• By atomic mass

• By number of electrons

• By atomic number

• By number of neutrons

What did Henry Moseley discover in 1913 about organizing elements?

• By number of protons

• By atomic number

• By number of electrons

• By atomic mass

What did Mendeleev predict that was later confirmed with the discovery of elements like gallium and germanium?

• Chemical properties of elements

• Atomic number of elements

• Physical state of elements

• Atomic weight of elements

According to the periodic law, elements in the same vertical column (groups) have similar:

• Atomic mass

• Atomic number

• Chemical properties

• Physical state

What did Henry Moseley use to study elements and make his discovery in 1913?

• Spectrometer

• Telescope

• X-rays

• Microscope