The Atom and Periodic Table

Why is the mass number a decimal?

- Mass Number is the weighted average of all the isotopes of an atom - The isotope whom mass number is closest to the actual mass number is more abundant

How do I find items?

- Number of Protons = Atomic Number - Number of Electrons = Number of Protons (Because Atoms are neutral which means positive equals negative) - Number of Neutrons = Mass Number subtract Atomic Number

What is the mass of a proton?

1 amu

An atom has an atomic number of 15 and a mass number of 31. How many protons are there in the atom?

15

What Period is Lithium in?

2

Which is the electron arrangement for sodium? A. 11 B. 2, 8, 1 C. 22.990 D. 12

2, 8, 1

An aluminum isotope consists of 13 protons, 13 electrons, and 14 neutrons. Its mass number is

27

How many Electrons are in one atom of Lithium?

3

How many Protons are in one atom of Lithium?

3

What is the Atomic Number of Lithium?

3

An atom has an atomic number of 30 and a mass number of 65. How many neutrons are in the atom?

35

How many Neutrons are in one atom of Lithium?

4

An atom has 5 protons and 7 neutrons. What is the atomic number of the atom?

5

What is the Atomic Mass of Lithium?

6.941

How many Protons+Neutrons are in one atom of Lithium?

7

- Group IA - 1 valence electron - Reactivity increases from top to bottom - Francium is most reactive metal

Alkali Metals

- Group IIA - 2 valence electrons - Ca: is in your bones, teeth, shell

Alkaline Earth Metals

- Smallest particle of an element - Counting unit of elements

Atom

The smallest particle of an element that still retains the properties of the element

Atom

- Identifies the element - Number of Protons - Top of the Element Block - Do atoms have an overall charge? Therefore # of protons = # of electrons

Atomic Number

In the modern periodic table elements are arranged by:

Atomic Number

Number of protons in an atom's nucleus

Atomic Number

All atoms of the same element have the same

Atomic number

All matter is made of .....

Atoms

Which element is not a metal? A. Na B. Re C. Al D. B

B

- Focuses On Electrons - Places electrons into energy levels - Developed by Neil Bohr

Bohr's

- Group IIIA - 3 valence electrons - Al: most abundant metal in Earth's crust

Boron Family

Which is a halogen? A. Helium B. Chlorine C. Oxygen D. Neptune

Chlorine

Elements are classified as metals, nonmetals, or metalloids based on properties and location on the periodic table

Classifying Elements

- Called Groups - Go up and down

Column

Circles - Number of Circles = Period Number = Number of Energy Level Dots - Go on the Last Circle - Number of Dots = Number of Valence Electrons - Important Note: First energy level has a max of 2 electrons All other energy levels have a max of 8 electrons

Components of Bohr's Model

Believed in the atom

Democritus

The particle that moves around the nucleus is a(n) .

Electron

Which of the following is a negatively charged subatomic particle? A. Electron B. Proton C. Neutron D. Quark

Electron

Area around the nucleus of an atom where the atom's electrons are most likely to be found

Electron Cloud

Uses the symbol for an element and dots representing the number of electrons in the element's outer energy level.

Electron Dot Diagram

- Model of an atom in which each dot represents the valence electrons - AKA: Lewis Dot Diagrams

Electron Dot Diagrams

Current model of the atom

Electron cloud model

- Negatively charged - Symbol = e- - Extremely small mass

Electrons

Particles surrounding the center of an atom that have a charge of 1-

Electrons

Substance with atoms that are all alike

Element

- A substance that cannot be broken down into simpler substances - Ex: Neon, Gold, Helium

Elements

- Around the nucleus - Contains the electrons

Energy Levels/Shells/Orbitals

Found the nucleus

Ernest Rutherford

Vertical column in the periodic table

Group

- 18 groups - Elements in the same group have the same: Properties Valence Electrons Oxidation Numbers

Groups

Vertical columns on the periodic table are called __.

Groups or Families

- Group VIIA - 7 valence electrons - Salt formers - Reactive with metals - Fluorine: most reactive nonmetal

Halogens

- Charged Particles Negative Charge = gains electrons Positive Charge = lose electrons

Ions

Charged particle that has either more or fewer electrons than protons

Ions

- Atoms of the same element that have the same atomic number but different mass numbers - # of protons stays the same - # of neutrons change

Isotopes

Atoms of the same element that have different numbers of neutrons

Isotopes

Found the electron

JJ Thomson

Made the theory on atoms

John Dalton

- The sum of the Protons and Neutrons (electrons virtually no mass) - Bottom Number of the element block - Round to the Nearest Whole Number

Mass Number

Sum of the number of protons and neutrons in an atom's nucleus

Mass Number

Isotopes are atoms of the same element that have different

Masses

Element that typically is a hard, shiny solid, is malleable, and is a good conductor of heat and electricity

Metal

Elements which are shiny, conduct electricity and heat are called

Metal

Is Lithium a Metal, Non-Metal, or Metalloid?

Metal

Element that shares some properties with metals and some with nonmetals

Metalloid

- Have BOTH characteristics of metals and nonmetals - Found on the stair-step line - What are the Metalloids B, Si, Ge, As, Sb, Te, Po, At

Metalloids

The atoms along the staircase in a periodic table are called

Metalloids

- Most elements - Good Conductors of electricity/heat - Solid at room temperature (except Mercury) - Ductile: turn into thin wire - Luster: reflect light - Malleable: hammer into sheets - High Melting Point - Left side of the stair step - Francium: Most reactive metal - High Boiling Point

Metals

Established energy levels

Neil Bohr

Neutral particle, composed of quarks, inside the nucleus of an atom

Neutron

Which of the following is a subatomic particle with a neutral that is found in the nucleus of an atom? A. Electron B. Proton C. Neutron D. Quark

Neutron

- No charged (neutral) - Symbol = n - Mass = 1 amu

Neutrons

What carries no charge

Neutrons

- Group VA - 5 valence electrons - N is 78% of air - Main component of fertilizer

Nitrogen Family

- Group VIIIA - 8 valence electrons - Stable = not reactive - Inert Gases - All Shells are full

Noble Gases

Which group of the periodic table is composed of inert (not reactive) gases?

Noble Gases

Element that usually is a gas or brittle solid at room temperature, is notE malleable or ductile, is a poor conductor of heat and electricity, and typically is not shiny.

Nonmetal

- Dull - Brittle - Poor Conductors of electricity/heat - Most are gas at room temperature - Low Melting Point - Low Boiling Point - Right Side of Stair Step - Fluorine: most reactive nonmetal

Nonmetals

- Center of the atom - Small, dense, positively charged - Where Protons and Neutrons remain

Nucleus

Positively charged center of an atom that contains protons and neutrons and is surrounded by a cloud of electrons

Nucleus

- Number of electrons an atom will gain or lose to become stable - Stable = 8 electrons on last shell - Code: +1, +2, +3, ±4, -3, -2, -1, 0 - "+" means lose electrons - "—" means gain electrons

Oxidation Number

Positive or negative number that indicates how many electrons an atom has gained, lost, or shared to become stable.

Oxidation Number

- Group VIA - 6 valence electrons - O: most abundant element in Earth's crust

Oxygen Family

Horizontal row in the periodic table

Period

- An arrangement of elements in columns based on properties that repeat from row to row - Modern Periodic Table arranged by Henry Moseley Arranged by increasing atomic number

Periodic Table

Organized list of all known elements that are arranged by increasing atomic number and by changes in chemical and physical properties.

Periodic Table

- Reactivity As you go left to right across a period, the less reactive elements become Going down a group, the more reactive the element becomes

Periodic Trend

- 7 periods - Elements in the same period have: Same number of energy levels or shells or orbitals

Periods

Particle, composed of quarks, inside the nucleus of an atom that has a charge of 1+

Proton

Which of the following is a positively charged subatomic particle found in the nucleus of an atom? A. Electron B. Proton C. Neutron D. Quark

Proton

- Positively charged - Symbol = p+ - Mass = 1 amu

Protons

An element's identity is determined by the number of

Protons

What is in the nucleus of an atom?

Protons and neutrons

Which of the following includes all of the subatomic particles found in the nucleus of an atom? A. Electrons and protons B. Electrons, protons, and neutrons C. Neutrons and electrons D. Protons and neutrons

Protons and neutrons

Periodic means ___.

Regular repeating pattern

- Called Periods - Go across

Rows

Which is an alkali metal? A. Magnesium B. Iron C. Sodium D. Europium

Sodium

Is Lithium a Solid, Liquid, or Gas?

Solid

1. Place a dot to be Nucleus 2. Place circles around Nucleus 3. Place dots on last circle in correct order

Steps to Draw Bohr's Model

1. Identify the number of valence electrons 2. Write the element's symbol 3. Place dots around the symbol equal to valence electrons in correct order

Steps to Draw Dot Diagrams

- THE MIDDLE OF THE PERIODIC TABLE - Groups 3B-12B - Vary in oxidation numbers - Brightly colored - Likes to combine with Oxygen

Transitional Metals

- Number of electrons on the outermost (last) energy level - Code: 1, 2, 3, 4, 5, 6, 7, 8 - Number next to "A" at the top of the column

Valence Electrons

Is copper an element on the periodic table?

Yes

What Group is Lithium in?

alkali metals (1A)