Chemistry Periodic Table
How do you write the shorthand configuration of electrons?
(1) Write the Symbol of the Noble Gas element from the row before it in brackets [ ]. (2) Add the remaining electrons by starting at the s orbital of the row that the element is in until the configuration is complete.
If an electron is removed from a sodium (Na) atom, what charge does the Na cation have?
+1
If two electrons are removed from a Magnesium (Mg) atom, what charge does the Mg cation have?
+2
What is Zeff for Boron (B)?
+3
What is the effective nuclear charge on electrons in the outer most shell for Aluminum?
+3
What is the effective nuclear charge, Zeff on electrons in the outer most shell for Boron?
+3
What are the 4 main trends in the periodic table?
-Radius of atoms -Electronegativity -Ionization Energy -Metallic Character
What is the shielding constant, S, for Aluminum (Al)?
10
Give the atomic number of the element with the smallest radius in the 2nd period.
10 (Ne)
What is the atomic number for the element in period 3, group 16?
16
How many valence electrons does magnesium have?
2
What is the shielding constant, S, for Boron (B)?
2
How would you calculate the force for helium using Coulomb's Law?
2ke^2/r^2=F -because the Zeff is 2
What is the atomic number for the element in period 5, group 3?
39
What is Zeff for Carbon (C)?
4
In which subshell does an electron in an arsenic (As) atom experience the greatest shielding?
4p
Which noble gas has the lowest first ionization energy (enter the atomic number)? A 1 B 10 C 2 D 86
86
Explain why radius decreases across a period.
Across a period, effective nuclear charge increases while energy level remains the same. The force of attraction between the nucleus and valence electrons gets stronger. Valence electrons are pulled in tighter, so radius gets smaller.
Two elements are studied. One with atomic number X and one with atomic number X+1. It is known that element X is a Noble Gas. Which group on the periodic table is X+1 in?
Alkali Metals
An unknown element has an electron configuration ending in s2. It is most likely in which group?
Alkaline Earth Metals
To which group on the periodic table does Beryllium belong?
Alkaline Earth Metals
What is the relationship between force of attraction and ionization energy?
As force increases, ionization energy increases.
What is the trend in atomic size down a group?
Atomic radius gets larger as move down a group
What is the trend in atomic size across a period?
Atomic radius gets smaller as you move right across a period
How are elements listed on the periodic table?
Atoms are listed on the periodic table in rows, based on number of protons.
What are neutral atoms?
Atoms that have the same number of electrons and protons.
Compare the radial size of carbon to boron and nitrogen.
B>C>N
How do electrons move from the s sublevel to the d or f sublevel and why?
Because of how close the f and d orbitals are to the s orbitals, very little energy is required to move an electron from the s orbital (leaving it half full) to the f or d orbital, causing them to also be half full; this is to allow the element to exist in a more stable state
How can the magnitude of the force between the protons in the nucleus and electrons in the orbitals be calculated?
Can be calculated using Coulomb's Law.
Of the following elements, which has the largest first ionization energy? Na, Al, Se, and Cl
Cl
What are columns called in the periodic table?
Columns in the periodic table are called Groups. -Groups are sometimes referred to as Families, but "groups" is more traditional.
The most stable atoms have what?
Completely full energy levels.
Which one of the following atoms has the largest radius? A Cs B Al C Be D Ne
Cs
Explain why radius increases down a group.
Down a group, effective nuclear charge remains the same while the energy level increases. The increased distance from the nucleus to valence electrons makes the force of attraction decrease. Electrons are not held as tightly, so radius gets larger.
Elements in the same groups, with the same chemical properties have very similar what?
Electron configurations.
Stability is due to what?
Electron configurations.
Two elements are studied. One with atomic number X and one with atomic number X+1. Assuming element X is not a Noble Gas, which element has the larger atomic radius?
Element X
Two elements are studied. One with atomic number X and one with atomic number X+1. It is known that element X is a Noble Gas. Which element has the larger atomic radius?
Element X+1
Which one of the following atoms has the smallest radius? A O B F C S D Cl
F
Which of the following correctly lists the five atoms in order of increasing size (smallest to largest)? O, S, Ba, Mg, F
F < O < S < Mg < Ba
Which of the following equations correctly calculates the Coulombic force between the valence electrons and the nucleus of an oxygen atom?
F = 6ke^2/r^2
Next in order of stability are elements with what?
Full sublevels.
What is the importance of the discontinuity between groups 15 and 16?
Group 15 is more stable because it has a 1/2 filled sublevel and therefore requires more ionization energy to remove electrons.
Where are chalcogens (the oxygen family) located?
Group 16; they are the elements of fire
Where are halogens located? Are they reactive?
Group 17; they are highly reactive nonmetals
Where are noble gases located? Are they reactive?
Group 18; they are nearly inert, or in other words, non reactive
Where are alkali metals located? Are they reactive?
Group 1; they are very reactive
Where are alkaline earth metals located? Are they reactive?
Group 2; they are reactive
Of the elements below, __________ has the largest first ionization energy. H, Li, K, and Rb
H because it is the highest in the group and ionization energy decreases as you move down a group.
Finally, the elements with what are also stable?
Half full sublevels are also stable but not as stable as elements with fully energy levels or sublevels
The elements in the periodic table which lack one electron from a filled shell are referred to as ___.
Halogens
To which group on the periodic table does Fluorine belong?
Halogens
To which group on the periodic table does Iodine belong?
Halogens
How an element reacts depends on what?
How its electrons are arranged
There are basic exceptions in electron configurations in which sublevels?
In the d and f sublevels.
What happens to ionization energy down a group?
Ionization energy decreases as you go down a group, because the radii become larger and the force is consequently lower... it is easier to pluck electrons off of the shell.
What happens to ionization energy across a period?
Ionization energy increases across a period.
Compare the radial size of boron to lithium and beryllium.
Li>Be>B
What did Dmitri Mendeleev argue?
Mendeleev argued that elemental properties are periodic functions of their atomic weights.
What is the importance of discontinuity #1?
More energy is required to remove an electron from Group 2 elements than Group 13 elements.
Which one of the following atoms has the smallest radius? A Fe B N C S D I
N
Of the following, which gives the correct order for atomic radius for Mg, Na, P, Si and Ar?
Na > Mg > Si > P > Ar
Which of the following would have the highest effective nuclear charge?
Neon
The electron configuration ending ns2p6 belongs in which group of the periodic table?
Noble gases
The elements in the periodic table that have completely filled shells or subshells are referred to as:
Noble gases
To which group on the periodic table does Neon belong?
Noble gases
Of the following atoms, which has the largest first ionization energy? Br, O, C, and P
O
The Periodic Table of Elements contains what kind of information about every element that matter can be made of in the Universe?
Physical and chemical
What kind of atom is formed when an electron is removed?
Removing an electron creates a positively charged atom called a cation.
What are rows called in the periodic table?
Rows in the periodic table are called Periods.
Inner electrons are doing what for the valence electrons?
Shielding them from the nucleus
Compare ionization energies for magnesium, aluminum and silicon.
Silicon> Aluminum> Magnesium
According to Coulomb's Law, the stronger the charge of the objects, the ___ the force between the objects.
Stronger
Where are transition metals located? Are they reactive?
The d block or groups 3-12; they have low reactivity
What is the "discontinuity #1" in ionization energy?
The electron removed for Group 13 elements is from a p orbital and removing this electron actually adds stability. The atom gains stability by having a full s orbital, and an empty p orbital. (Group 2 and Group 13)
What is the first ionization energy?
The energy required to remove the first electron.
What is the second ionization energy?
The energy required to remove the second electron
What is ionization energy?
The ionization energy is the amount of energy required to remove an electron from an atom.
In a multielectron atom, electrons are both attracted to the positive nucleus and repelled by other electrons. The nuclear charge that an electron experiences depends on both factors. What is an example of this?
The valence electron of sodium is attracted to the positive nucleus but is repelled by the negative inner electrons.
Which of the following elements has the largest amount of inner shell electrons: aluminum, silicon or phosphorus?
They all have the same number of inner shell electrons
Two elements are studied: one with atomic number X and one with atomic number X+1. Assuming element X is not a noble gas, which element has the larger shielding constant?
They are both the same because they would be in the same shell
To which group on the periodic table does Iron belong?
Transition Metals
The electron configuration [Ar]4s23d5 belongs in which group of the periodic table?
Transition metals
These outer electrons are called what?
Valence electrons.
What are the two main ways we are able to group elements?
We are able to group them based, not only on the properties they present when in isolation, but also the properties they reveal when exposed to other elements or compounds.
What do we know now that Mendeleev did not know?
We now know that element properties are periodic functions of their atomic number.
According to Coulomb's Law, the greater the distance between two objects, the ___ the force between the objects.
Weaker
The formula for effective nuclear charge is: Zeff = Z-S What does each variable in this equation stand for?
Z is the atomic number (the number of protons). S is the shielding constant, the number of inner electrons that shields the valence electrons from the protons.
The electron configuration for Copper (Cu) is
[Ar] 4s^1, 3d^10
What would be the shorthand electron configuration for Silver (Ag)?
[Kr]5s^1, 4d^10
What would be the shorthand electron configuration for Molybdenum (Mo)?
[Kr]5s^14d^5
What would be the expected "shorthand" electron configuration for Sulfur (S)?
[Ne]3s^2,3p^4
Atomic radius generally increases as we move __________.
down a group and from right to left across a period
Elements in each group on the Periodic Table have similar ___.
electron configurations
Across a period from left to right Zeff ___.
increases
The elements in the Periodic Table are arranged from left to right in order of increasing ___.
number of protons and electrons
Down a group from top to bottom Zeff ___.
remains the same
What is electronegativity?
the ability of an atom to attract other electrons.
Alkaline earth metals are more stable than alkali metals because...
they have a full subshell
