key terms
key terms cont.
key concepts assessment
100

what is atomic mass?

The atomic mass is the average mass of all the isotopes in a element.

100

what is plasma?

Plasma is a state of matter that consists of a gas-like mixture of free electrons and nuclei of atoms that have been stripped of electrons.

100

How did Mendeleev discover the pattern that led to the periodic table?

He noticed that a pattern of properties appeared when he arranged the elements in order of increasing mass.

200

what is the periodic table?

In the periodic table used today, the properties repeat in each period, or row.

200

what is nuclear fusion?

Nuclear fusion is a process in which two atomic nuclei combine, forming a larger nucleus and releasing huge amounts of energy.

200

what information about the elements does the periodic table provide?

the properties of an element can be predicted from its location in the periodic table.

300

what is the period?

The periodic table is organized in horizontal rows known as periods.

300

what is a chemical symbol?

Just below the atomic number are the letters Fe, the chemical symbol for iron.

300

How are the elements created?

in this book, each square includes the elements' atomic number, chemical symbol, name, and atomic mass.

400

what is a group?

As a result of the repeating pattern of properties, the elements of the modern periodic table fall into 18 vertical columns, or groups.

400

name the parts of the figure

(use textbook for gold's periodic table)

element: 79
AU: chemical symbol

atomic mass:196.967