Atoms And The Periodic Table

Question 1

Nucleus

Answer 1

Center of the atom. Made of protons and neutrons.

Question 2

Proton

Answer 2

In the nucleus. Positive charge.

Question 3

Neutron

Answer 3

In the nucleus. No charge.

Question 4

Electron

Answer 4

Moving around outside the nucleus in a cloud. Negative charge.

Question 5

Orbital

Answer 5

The regions in an atom where electrons are likely to be found.

Question 6

Valence Electron

Answer 6

An electron in the outermost energy level of an atom.

Question 7

Periodic Law

Answer 7

States that when elements are arranged by the number of protons, similarities in their properties will occur in a regular pattern.

Question 8

Period

Answer 8

Horizontal rows in the periodic table.

Question 9

Group

Answer 9

Columns in the periodic table.

Question 10

Ion

Answer 10

Has a net electrical charge because the charges do not cancel completely as they did before.

Question 11

Atomic Number

Answer 11

Tells how many protons are in an atom.

Question 12

Mass Number

Answer 12

The number of protons plus the number of neutrons.

Question 13

Isotope

Answer 13

Different version of an element. Different mass, but the same element because they have the same number of protons.

Question 14

Atomic Mass Unit (amu)

Answer 14

Equal to exactly 1/12 of a carbon-12 atom.

Question 15

Average Atomic Mass

Answer 15

A weighted average.

Question 16

Metal

Answer 16

Most metals are shiny solids that can be stretched and shaped.

Question 17

Nonmetal

Answer 17

All, but hydrogen, are found on the right side of the periodic table. May be solids, liquids, or gases. Solid nonmetals are typically dull and brittle and are poor conductors of heat and electricity.

Question 18

Semiconductor

Answer 18

Can conduct under certain conditions.

Question 19

Alkali Metal

Answer 19

Soft and shiny and reacts violently with water.

Question 20

Alkaline-Earth Metal

Answer 20

Have two valence electrons.

Question 21

Transition Metal

Answer 21

Found in groups 3-12 on the periodic table. Most are combined with other elements as an ore.

Question 22

Halogen

Answer 22

Found in group 17. Form salts when they react with metals.

Question 23

Noble Gas

Answer 23

Found in group 18. Exist as single atoms instead of molecules.

Question 24

Mole

Answer 24

Large counting unit. A collection of a very large number of particles. About 6.022 x 10^23.

Question 25

Avoagdro’s Constant

Answer 25

The number of particles, 6.022 x 10^23, in exactly one mole of a pure substance.

Question 26

Molar Mass

Answer 26

The mass in grams of 1 mole of a substance.

Question 27

Conversion Factor

Answer 27

A ratio that is derived from the equality of two units that can be used to convert from one unit to another.