Name: _________________________
Date: _____________ Period:______
Chemistry: The Periodic Table
Directions: Answer each of the following questions. You need not use complete sentences.
What is a period? How many are there in the periodic table?
A period is a row of elements on the periodic table, in which the elements are ordered
one proton more each place from left to right. A period also often helps to represent an
electron energy level and the order in which electrons are filled into their sublevels. There
are 7 periods.
What is a group (also called a family)? How many are there in the periodic table?
Groups are the columns that are found top to bottom in the table. They show elements
that have the same sublevel and number of electrons in their outer shell, valence
electrons. Often elements in a group share any similar chemical properties because of
this. There are 18 groups in the periodic table.
State the number of valence electrons in an atom of:
a. sulfur
6
b. calcium
2
c. chlorine
7
d.arsenic
5
Give the names and chemical symbols for the elements that correspond to these atomic
numbers:
a. 10
b. 18
c. 36
d. 90
Neon, Ne
Argon, Ar
Krypton, Kr
Thorium, Th
List, by number, both the period and group of each of these elements.
Symbol
Period
Group
a. beryllium
Be
2
2
b. iron
Fe
4
8
c. lead
Pb
6
14
Which of the following pairs of elements belong to the same period?
a. Na and Cl
b. Na and Li
c. Na and Cu
d. Na and Ne
Which of the following pairs of elements belong to the same group?
a. H and He
b. Li and Be
c. C and Pb
d. Ga and Ge
Would you expect strontium to be, chemically, more similar to calcium or rubidium and WHY?
Calcium, because they share a common amount of valence electrons. Valence electrons are the
main contributor to chemical properties and how elements interact with other matter. Both
strontium and calcium have two electron on the the “s” sublevel, 5s2 and 4s2
What are the Group 1 elements called?
Alkali metals
What are the Group 2 elements called?
Alkaline earth metals
What are the Group 17 elements called?
Halogens
What are the Group 18 elements called?
Noble Gases
Which alkali metal belongs to the sixth period?
Caesium
Which halogen belongs to the fourth period?
Iodine
What element is in the fifth period and the eleventh group?
Palladium
Why do all the members of a group have similar properties?
They have similar properties, because they share similar amounts of electrons in their
outer shell, valence electrons! This means they will only be able to interact with other
elements with those electrons so they often show similar properties.
What do we mean by the “atomic radius?”
Atomic radius describes the relative size of our atoms by looking at how much distance is
between two nuclei of two atoms of the same element when they are bonded together.
Within a group, what happens to the atomic radius as you go down the column?
Atomic radius becomes greater typically as you go down a group.
Within a period, what happens to the atomic radius as the atomic number increases?
As the atomic number increases, yet the electrons remain in the same energy level, we
will notice the radii of our atoms decrease as we go left to right in a period. So larger
atomic number means more positive pull means smaller electron clouds in each period.
What is” Ionization Energy?”
The energy necessary to remove an electron from an atom of a certain element.
What happens to the ionization energy as you move down a group?
The ionization energy becomes less.
What happens to the ionization energy as you move from left to right across the periodic table?
The ionization energy becomes greater.
What is “electronegativity?”
A measurement of the ability of an atom to pull electrons more towards it when in a
chemical compound.
What happens to electronegativity as you move down a group?
It often becomes less
What happens to the electronegativity as you move from left to right across the periodic table?
It often becomes greater.
Where, generally, are the metals located on the periodic table?
Two thirds of the table starting from the left.
Where, generally, are the nonmetals located on the periodic table?
One third the table starting from the right.
What group has 7 valence electrons?, list the symbols of the elements
Group 17, Halogens, F, Cl, Br, I, At
What group has only 1 valence electron? List the elements.
Group 1, mostly Alkali Metals, H, Na, K, Rb, Cs, Fr
Which would you expect to be more electronegative Hydrogen or Fluorine? Why?
Fluorine, it is further to the left and at the top of the table, which follow the trend with electronegativity.