Chapter 3 Study Guide7th Grade

An elements properties can be predicted from its

Location in the periodic table

2. In the ___ state of matter, electrons are stripped away from the nuclei.

Plasma

If a substance is _______, it can be pulled or drawn into a wire.

ductile

The sun and many other stars are made mostly of the element

hydrogen

A(n) _______is a positively charged particle in an atom’s nucleus.

proton

Which of the following is NOT a characteristic of most metals?

brittle

An element’s _______ tells the number of protons in its nucleus.

atomic number

Dmitri Mendeleev created the first

periodic table

The particle that are lost, gained, or shared in chemical reactions are

electrons

A(n) ________has some of the properties of both metals and nonmetals.

metalloid

A(n) __________consists of two nonmetal atoms bonded together.

Diatomic molecule

12. The family of ________is the most reactive group of metals in the periodic table. Alkali metals

13. The ______ and the _____ are shown at the bottom of the periodic table in order to keep the table a reasonable size.

Lanthanides; actinides

A mixture of metals is called a(n) ____________.

alloy

The _______family is a very reactive group of nonmetals whose atoms gain or share one electron in chemical reactions.

halogen

Metals are good conductors of heat and electricity.

From left to right in the periodic table, the elements are arrange in order of increasing atomic mass.

The mass of a proton is about one atomic mass unit.

The reactivity of the metal elements generally decreases as you move from left to right across the periodic table.

Helium nuclei and energy are the products of the nuclear fusion of the sun’s hydrogen.

Essay question: 5 points*pick one of the following topics*answer in complete, well written sentences

*In the periodic table, the transition metals, such as chromium, iron, and copper, are located between the reactive alkali earth metals on the far left and the less reactive metals and other elements on the right side. Describe three properties of the transition metals. * What is a supernova and how is it related to the matter found on Earth?*What information can be found in a square of the periodic table? What does each piece of information mean?