Chapter 12 lesson 2

Rows of elements are called

• atomic number

• periodic table

• groups

• periods

The ______________ make up the columns of the table.

• period

• group

• periodic table

• element

The _______________ that we use today

organizes the elements by repeating patterns in their properties.

• period

• group

• periodic table of the elements

• atom

Not lustrous (dull appearance)

• Poor conductors

• Brittle

• May be solid, liquid or gas at room

temperature

Less reactive

• metal

• nonmetal

• metalloid

• atomic number

The ____________of an element is the

number of protons in its nucleus

• atomic number

• noble gases

• atomic mass

• element

A _______________may be either one capital letter or a combination

of one capital and one lowercase letter for the name of an element.

• noble gases

• chemical symbol

• atomic number

• atomic mass

Have properties of both metals and

nonmetals

• Lustrous (shiny appearance)

• Semi-conductors

• Form alloys with metals

• metalloids

• nonmetal

• metal

• noble gases

Lustrous (shiny appearance)

• Good conductors

• Ductile (can be made into a wire)

• Malleable (can be bent and shaped)

• Usually solids at room temperature

(mercury is the exception)

Very active

• metalloids

• nonmetal

• metal

• Mrs. Joseph

He created a table

of elements organized by atomic mass.

• Dmitri Ivanovich Mendeleev

• Robert Boyles

• Nirva Joseph

• Henry Moseley

In 1913, _________________ ordered the elements

by atomic number.

• Robert Boyle

• Henry Moseley

• Mrs. Joseph

• Jabir ibn Hayyan