12/15 -Unit Review: Atoms

1

A(n) _______  is the smallest piece of an element that still represents that element.

1

In the nucleus are _______ , which are atomic particles with a positive charge.

1

James Chadwick discovered the _______ , a particle in the nucleus with neutral/zero charge.

1

The atomic model by Neils Bohr proposed that _______  move in circular orbits, or energy levels  around the nucleus.

1

In the modern atomic model, electrons form a(n) _______  which is an area around the nucleus in  which an electron is likely to be located.

1

The atomic number is the number of _______  in one atom of an element.

1

The mass number is the total number of _______  and _______  in one atom of an element.

1

In a neutral atom, the number of _______  must equal the number of _______ .

1

-- _______  are atoms of the same element that have different numbers of neutrons.

1

Around 1868, Russian chemist _______ created the _______  to help classify the known  elements by their physical and chemical properties.

1

In the periodic table, a column is called a _______  and a row is called a _______ .

1

Elements in the same _______  have similar chemical properties.

1

Most elements in the PT are _______ , which have a shiny luster and are good conductors.

1

-- _______  are on the right side of the PT; which have properties opposite of metals.-

1

Between the metals and nonmetals are the _______ , which have properties of both.

1

Even though the atom is made of charged particles, it is still neutral. Explain why.