Periodic Table Trends

The Russian scientist, Dmitri Mendeleev, noticed that by arranging the elements known at his time in order of increasing _____________, similarities in the chemical properties appeared at regular intervals.

• atomic mass

• atomic number

• group number

• period number

Mendeleev predicted that spaces left in his periodic table represented

• isotopes.

• radioactive elements.

• noble gases.

• undiscovered elements.

Based on evidence collected since Mendeleev's time, elements on the modern periodic table are arranged in order of __________.

• mass number.

• atomic number.

• average atomic mass.

• group number.

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

• atomic masses.

• atomic radii.

• atomic numbers.

• ionic charges.

What periodic group includes argon, krypton, and xenon?

• noble gases

• halogens

• alkaline earth metals

• actinides

Elements in a group of the periodic table can be expected to have similar

• properties.

• atomic masses.

• number of neutrons.

• atomic numbers.

Each period on the periodic table corresponds to

• a sublevel.

• atomic mass.

• atomic number.

• an energy level.

The horizontal rows on the periodic table are called

• groups.

• periods.

• families.

• an octet.

Calcium, Ca, and arsenic, As, belong to

• group 17

• period 4

• group 2

• period 3

The electron configuration for phosphorus is 1s²2s²2p⁶3s²3p³. Phosphorus is in period

• 2

• 3

• 5

• 15