Chemistry periodic table review

periodic table review

Who is considered the father of the periodic table and how did he arrange the precursor to our modern day periodic table? At the time, many other scientists were trying to organize the known elements, but this person is given credit for the periodic table. What was significant about his work?

Who is considered the father of the periodic table and how did he arrange the precursor to our modern day periodic table? At the time, many other scientists were trying to organize the known elements, but this person is given credit for the periodic table. What was significant about his work?

Mendeleev’s Periodic Table was organized by increasing atomic weight and he grouped elements with similar physical and chemical properties. Mendeleev also predicted properties of unknown elements and was correct!

List the properties of metals and nonmetals.

Metals: have luster, conduct electricity, form cations, react with acid, malleable, ductile. Nonmetals: dull, brittle, do not react with acid, not conductors, form anions.

List the metalloids. What is significant about metalloids?

Metalloids have properties of both metals and nonmetals.

List the diatomics (names and correct formulas).

Hydrogen, oxygen, nitrogen, chlorine, bromine, iodine, fluorine

H₂ O₂ N₂ Cl₂ Br₂ I₂ F₂

Which two elements are liquids at room temperature and pressure?

The two liquids at room temperature and pressure are bromine (nonmetal) and mercury (metal).

Do elements in the same period or the same group have similar properties? Why?

yes because they have the same number of valence electrons.

Where are the transition metals located? What kind of ions do they form?

The transition metals are located in the middle of the periodic table. They can form multiple kinds of cations.

Why are the rare earth metals at the bottom of the table? Where do they fit in the table? In which period are the lanthanides located? The actinides?

The rare earth metals (also known as the inner transition metals) are located at the bottom for convenience sake. They fit into the table and are a part of periods 6 and 7

Atomic size (increases or decreases) as you move across the periodic table from left to right. Explain

Size DECREASES due to greater attraction (increase in atomic number - which is the number of protons) between nucleus and electrons.

Atomic size (increases or decreases) as you move from top to bottom of a group of the periodic table. Explain

Size INCREASES due to increasing energy levels.

Why are cations smaller than neutral atoms? Why are anions larger than neutral atoms?

Cations are smaller than neutral atoms because when a neutral atom loses its electrons, it also loses an entire energy level. In addition, the protons outnumber the electrons and are able to pull them in closer to the nucleus. Anions are larger than neutral atoms because the electrons spread out to accommodate additional negative charges. In addition, there are fewer protons and cannot pull the electrons in as tightly.

Ionization Energy (increases or decreases) as you move across the periodic table from left to right. Explain

Ionization Energy INCREASES due to increase in atomic number and the increase amount of valence electrons. Atoms want to satisfy the octet rule.

Ionization Energy (increases or decreases) as you move from top to bottom of a group of the periodic table. Explain

Ionization Energy DECREASES due to larger size. The electrons are further away from the positive nucleus, making them easier to remove.

Electron Affinity (increases or decreases) as you move across the periodic table from left to right. Recognize that noble gases have low electron affinities because they already have 8 valence electrons and do not want any more. Explain

As atomic numbers increase, nuclei become more positive, attracting electrons. Nonmetals want to gain electrons to satisfy the octet rule.

Electron Affinity (increases or decreases) as you move from top to bottom of a group of the periodic table. Explain

As energy levels increase, electrons are further away from the nucleus. Shielding also prevents the outermost electrons from feeling the full effect of the nucleus. The noble gases all have a value of zero because they cannot accommodate any more electrons.

Which main group is not included in the electron affinity trend? Why?

Recognize that noble gases have low electron affinities because they already have 8 valence electrons and do not want any more.

Why are electron affinity values negative?

The negative sign is a notation that energy is released. A positive sign (like ionization energies) indicate that energy is required for the process to occur.

What are the symbols of the four quantum numbers? What information does each quantum number give us?

The 1st quantum number is the principal quantum number. It tells us which energy level the electron is located in.

The 2nd quantum number is the angular momentum quantum number and tells us the shape of the orbital.

The 3rd quantum number tells us the orientation in space of the orbital.

The 4th quantum number tells us the spin of the electron.

What are the shapes of the s, p, d and f subshells?

s = sphere

p = dumbbell

d = cloverleaf

f = splat

1. Explain the following concepts:

   1. The Aufbau Principle -

   2. The Pauli Exclusion Principle

1. The Aufbau Principle - electrons must fill lower energy levels first before filling higher energy levels

2. The Pauli Exclusion Principle - all electrons in an atom must have a unique set of quantum numbers

Who was the father of the periodic table and why is he credited rather than other scientists who were also working with this idea around the same time period

Mendeleev. He predicted the existence of undiscovered elements.

How many valence electrons do the following elements have? Silicon, helium, barium,carbon,hydrogen,iodine

Silicon (4), helium (2), barium (2), carbon (4), hydrogen (1), iodine (7)

What is the purpose of the staircase?

Separates the metals from the nonmetals

explain the difference between a group and a period

group (column)

period (row).

Which two elements are more chemically similar, fluorine and bromine or hydrogen and helium?

fluorine and bromine

Explain how effective nuclear charge relates to the trend of atomic size.

Electrons are attracted to the positive nucleus. The more the electron is attracted to the nucleus, the more tightly that electron is held by the nucleus. The more positive the nucleus, the closer the electron will be to it. Size will decrease.

Which has a greater ionization energy, phosphorus or titanium? WHY?

Phosporos, Ionization energy increases from left to right because of effective nuclear charge.

Which is larger, a sodium cation or a neutral sodium atom? WHY?

Neutral sodium atom, Cations are smaller than neutral atoms because they have lost an energy level

Which is larger, sulfur anion or a neutral sulfur atom? WHY?

Sulfur anion, Anions are larger than neutral atoms because of electron electron repulsion.

Which is smaller, helium or krypton? WHY?

Helium, Atomic radii increases moving from top to bottom of a group because each period represents another energy level or shell.

Which has a greater electron affinity, chlorine or potassium? WHY?

chlorine, Electron affinity increases moving toward the halogens because of effective nuclear charge.

Which block are the following elements in? carbon,yttrium,beryllium,americium

Carbon (p), yttrium (d), beryllium (s), americium (f)

Explain the difference between electron affinity and ionization energy

Electron affinity: (energy released when an electron is added)

Ionization energy: (energy required to remove an electron)