Atomic Structure

Period

A horizontal row of elements in the periodic table (same number of energy levels)

valence electrons

Electrons on the outermost energy level of an atom

Write in both hyphen and nuclear notation the most common isotope for lithium

lithium-7 7^L

Electron

negative particles outside of the nucleus in the electron cloud

Neutron

neutral particles in the nucleus with protons

Proton

positive particles in the nucleus

Quarks

smallest particle that makes up p+ and n

Mass number

tells the number of protons and neutrons in the nucleus of an atom.

Summarize our current understanding of atomic structure. Include the two parts, where the three particles are located, and where the mass and volume in an atom mainly exist.

Atom's are made up of nucleus and electron cloud is where the volume comes from.

Isotopes

Atoms of the same element that have different numbers of neutrons

Explain the three forces at work that hold an atom together.

Attractive force between the (+) nucleus and (-) electron cloud, repulsive force.

Draw a timeline of the discovery of the structure of the atom. Include date, name, and a brief summary of each discovery or model.

Democritus- first to name the atom John Dalton- Sphere model, atom is a solid sphere that can't get any smaller, elements are made of atoms have the same mass and compounds are atoms of different elements combine. Dmitri Mendeleev- developed the first periodic table, organized by atomic mass JJ Thomson- Plum pudding model, the atom is divisible, it is positively charged sphere with negative particles embedded throughout. Ernest Rutherford- Nuclear model, gold foil experiment, mass of an atom and its positively charged particles were in the nucleus, with low mass negatively charged particles surrounding it. Henery Moseley- discovered the number of protons is unique to each element arrange the periodic table. Niels Bohr- Bohr model, electrons are negative particles travel in orbits around the nucleus that is made of positive protons and neutrons. Schrodinger and Heisenberg- Electron cloud, nucleus is surrounded by an electron cloud that is divided into shells, but do not travel in fixed orbits.

Explain why elements in the same group have similar properties.

Elements in the same group have similar properties because they share similar amounts of electrons in their outer shell,valence electrons.

Explain the structure of the electron cloud. Include how many electrons are held on each level, where valence electrons are, and which electrons are the craziest

First you draw the nucleus and in it write you protons and neutrons. Then draw the first shell and it can only hold 2 electrons, and the second and third one holds only 8 electrons, the fourth shell holds 18. Valence electrons are in the outer most level and are the craziest.

List the names and any special characteristics for groups 1, 2, 3, 3-12, 17, and 18

Group 1- Alkali metals most reactive group 2- Alkaline earth metals Group 3- Rare earth metals group 3-12- Transition metals group 17- Halogens most reactive metals for nonmetals, reactivity decreases as you move down the group Group 18- noble gases nonreactive elements

Describe the pattern/shared characteristics of elements in the same group vs. the same period

Groups (vertical line) share the same # of electrons in their valence electron shell. Elements in the same period (horizontal line) have the same number of atomic orbitals.

Differentiate between the Bohr Model and the Electron Cloud Model.

The difference between the Bohr model and the electron cloud is that the Bohr model electrons travel in fixed orbits. While a electron cloud the electrons are divided into shells and do not travel in fixed orbits.

Differentiate between the characteristics of metals, nonmetals, and metaloids. Include their general location on the periodic table.

The metals are to the left of the line, its a good conductor, the nonmetals are to the right of the line and are poor conductors, the elements adjacent to the line are semi conductors.

Explain what it means for an atom to be electrically neutral.

The total electrical charges of the atom (+) (-) is therefore zero and the atom to be neutral.

Explain what two isotopes of the same element have in common and what is different about them. Include when an isotope is considered to be the most stable.

Two of the same isotopes of the same chemical element, different isotopes of an element have the same number of protons in the nucleus.

Groups

Vertical columns on the periodic table (valence electrons)

Which numbers tell you the following: a. The number of protons in an element b. The number of protons and neutrons in an element c. The number of total electrons d. The identity of an element e. The most common form of an element

a. atomic number b. mass number c. atomic number d. atomic number e. average atomic mass

Use the periodic table to determine the identity of each element described below. a. The first element in group 13. b. period 2 nonmetal with 6 valence electrons. c..A metalloid with 71 neutrons. d.A gas with 2 valence electrons and 1 energy level in its electron cloud.

a. boron b. oxygen c. antimony d. helium

Use the periodic table to determine the identity of each group described below. a.Their atoms have 5 valence electrons. b.They are the most reactive metals. c.They are the most reactive nonmetals. d.They do not react in nature.

a. nitrogen b. alkaline metals c. halogens d. noble gases

Atomic number

the number of protons in the nucleus of an atom

Atom

the smallest particle of an element that still has the properties of that element.

Average atomic mass

the weighted average of the atomic masses of the naturally occurring isotopes of an element