Periodicity

After Mendeleev constructed the periodic table, he predicted the discovery of several elements that were not yet known. What prediction was Mendeleev able to make about these unknown elements, based on his table?

• The unknown elements chemical and physical properties

• The likely geographical place on earth where the unknown elements could be found.

• The amount of the unknown element that could be found in mines and mineral deposits.

• Who would discover the unknown elements

• When the unknown lements would be discovered.

Tags

NGSS.HS-PS1-1

Considering the periodicity of the periodic table, what is the atomic number of Magnesium (Mg)

Tags

NGSS.HS-PS1-1

The horizontal rows are called

• periods

• family groups

What is the atomic mass of Lithium (Li)

Tags

NGSS.HS-PS1-1

How many protons does Potassium (K) have

Tags

NGSS.HS-PS1-1

Which statement describes the trends of electronegativity values in the periodic table?

• Values increase from left to right across a period and increase down a group.

• Values increase from left to right across a period and decrease down a group.

• Values decrease from left to right across a period and increase down a group.

• Values decrease from left to right across a period and decrease down a group.

Which physical property of elements is represented by y on the graph below?

• First ionization energy

• Ionic radius

• Atomic radius

• Electronegativity

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Which property generally decreases across period 3?

• Atomic number

• Electronegativity

• Atomic radius

• First ionization energy

Which series is correctly arranged in order of decreasing radius?

• A

• B

• C

• D

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Why does electronegativity increase as you go across a period?

• The number of energy levels decreases.

• The nuclear charge increases.

• The number of valence electrons decreases.

• The ionization energy decreases.

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2