Ch 4

Question 1

Each element has a unique name and is represented by a unique symbol

Answer 1

• Chemical symbol: a one- or two-letter designation for an element derived from the element’s name
• First letter of the symbol is always capitalized

Question 2

Father of the Periodic Table

Answer 2

Mendeleev

Question 3

Periodic Law of the Elements

Answer 3

when elements are arranged in a particular order (increasing atomic number), elements of similar properties occur at periodic intervals

Question 4

Elements are arranged into

Answer 4

• Groups/families – vertical columns

* Periods – horizontal rows

Question 5

Metals

Answer 5

Have luster, are malleable, conduct electricity

Question 6

Nonmetals

Answer 6

Do not have the properties of metals

Question 7

Metalloids

Answer 7

Have some metallic properties and some nonmetallic properties

Question 8

Atom

Answer 8

• The smallest individual particle of an element that maintains the properties of that element
• Atomos - indivisible

Question 9

Dalton’s Law of Atomic Theory

Answer 9

1. All matter is composed of extremely small particles called atoms.
2. Atoms of a given element are identical in their physical and chemical properties.
3. Atoms of different elements differ in their physical and chemical properties.
4. Atoms of different elements combine in simple, whole-number ratios to form compounds.
5. In chemical reactions, atoms are combined, separated, or rearranged but never created, destroyed, or changed.

Question 10

An atom is the smallest particle of an element that can exist and still have the properties of the element, known also as

Answer 10

. The fundamental building block of matter.

Question 11

Today, we know that atoms are made up of smaller, more fundamental particles called

Answer 11

subatomic particles

Protons, Electrons & Neutrons

Question 12

An atom consists

Answer 12

• Of a nucleus that contains protons and neutrons

* Of electrons in a large empty space around the nucleus

Question 13

An atom is composed of a nucleus and an area called the electron cloud

Answer 13

• The nucleus is very small compared to the size of the atom
• The nucleus contains the protons and the neutrons
• The electrons are constantly moving around in the electron cloud
• In a neutral atom, the number of electrons is equal to the number of protons

Question 14

The atomic number

Answer 14

Is specific for each element
Is the same for all atoms of an element
Is equal to the number of protons in an atom
Appears above the symbol of an element

Question 15

Ions

Answer 15

• Charged particles that have either lost or gained electrons
• These have the same number of protons and neutrons, but a number of electrons that differs from the number of protons

Question 16

Isotopes

Answer 16

Atoms of the same element (same number of protons) with different numbers of neutrons

Question 17

The mass of atoms is measured in units of

Answer 17

atomic mass unit

Question 18

Masses reported on the periodic table are

Answer 18

weighted averages

Question 19

The atomic mass of an element

Answer 19

• Is listed below the symbol of each element on the periodic table
• Gives the mass of an “average” atom of each element compared to 12C
• Is not the same as the mass number

Question 20

Mass Number

Answer 20

the number of protons plus the number of neutrons

Question 21

Atomic Weight/Mass

Answer 21

the mass of an average atom

Question 22

The calculation for atomic mass requires the:

Answer 22

• Percent (%) abundance of each isotope
• Atomic mass of each isotope of that element
• Sum of the weighted averages