In developing his periodic table, Mendeleev listed on cards each element's name, atomic mass, and

• atomic number.

• electron configuration.

• isotopes.

• properties.

Mendeleev's periodic table did not list all elements in order of increasing atomic mass because he grouped together elements with similar

• properties.

• atomic numbers.

• names.

• isotopes.

Mendeleev predicted that the gaps in his periodic table represented

• ions.

• radioactive elements.

• unstable elements.

• undiscovered elements.

The person who work led to a periodic table based on increasing atomic number was

• Moseley.

• Mendeleev.

• Rutherford.

• Cannizzaro.

The periodic law states that the physical and chemical properties of elements are periodic functions of their atomic

• masses.

• numbers.

• radii.

• structures.

Which group of elements was discovered by Strutt and Ramsay?

• lanthanides

• halogens

• noble gases

• actinides

A repeating pattern is referred to as

• unpredictable.

• irregular.

• periodic.

• a group.

On most periodic tables, the lanthanides and actinides appear

• on a separate page.

• below the main portion.

• on the back.

• at the top.

What is the difference in atomic number between He and Ne?

• 2

• 8

• 18

• 32

Which noble gas has the greatest atomic number?

• Ar

• Xe

• Kr

• Rn