Sc-6th-Ch4-Review

The most abundant element on Earth is ..............................., which is present in 46 percent of the matter on the planet.

• nitrogen

• carbon

• oxygen

• iron

Which of the following elements is not included in the group of elements that account for 90.5 percent of the matter on Earth?

• Phosphorus

• Silicon

• Iron

• Potassium

The chemical properties of an element depend on how its ............................... are organized.

• energy levels

• protons

• electrons

• neutrons

Which of the following symbols does not correspond to the element?

• Silver: Ag

• Gold: O

• Aluminum: Al

• Mercury: Hg

Calcium and phosphorous are indispensable for strong bones and teeth.

• True

• False

The elements are the basic units of matter because each of them is composed of different atoms.

• True

• False

To know which element an atom belongs to, the atom is identified by the number of electrons, or negatively charged particles, it possesses.

• True

• False

Electrons are negatively charged particles and are equal in number to the number of protons in an atom.

• True

• False

There are nineteen numbered groups in the periodic table.

• True

• False

Temperature and pressure determine if an element is in a solid, liquid, or gaseous state.

• True

• False