Mendeleev’s periodic table did not list all elements in order of in creasing 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 whose 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

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NGSS.HS-PS1-1

NGSS.HS-PS1-2

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

An element that has the electron configuration [Ne]3s²3p⁵ is in Period

• 2

• 3

• 5

• 7

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

An element that has the electron configuration [Ne]3s²3p⁵ is in Group

• 2

• 5

• 7

• 17

Tags

NGSS.HS-PS1-1