Did you know there are many different ways to use the periodic table to learn about the makeup or properties of elements? Continue reading to discover the many uses of the periodic table.
How Is the Periodic Table Structured?
There is a wide variety of information you can find just by looking at the periodic table. When taking your SATs, you will be provided with a periodic table indicating the atomic numbers and masses of elements. This periodic table is on the back of the instruction page.You will need to know how to properly read the periodic table to extract information from it, and this requires you to understand the structure of the periodic table.
It’s made up of rows, called periods, and columns, called groups. The elements are distributed across the periodic table according to their type and similar physical properties, creating a pattern in which the thee basic classifications of elements are clumped together. Let’s take a look at each of the element types and their common properties:
Metals represent the elements found below and to the left of the stair-step on the periodic table.
- They are great conductors of electricity and heat.
- They’re malleable, which means you can easily form them into different shapes.
- They’re very shiny.
- With the exception of mercury (Hg), they are all solid at room temperature.
- Chemically, metals are more than happy to give up electrons in their outer shell, called valence electrons, to form cations.
Nonmetals are elements found above the stair-step on the right side of the periodic table.
- They do NOT conduct electricity and heat very well.
- They can be a solid, liquid, or gas at room temperature.
- They are not very malleable and may break if you try to change their shape.
- Although very colorful, they tend to have a dull color.
- Chemically, nonmetals will happily accept valence electrons to form anions.
Metalloids, which sit between the metals and nonmetals, represent the honorable mention category. Think of these metals as a mixture between metals and nonmetals.
They are also referred to as semi-metals.
Patterns Within Groups
If you look more closely at the periodic table, you’ll see that there are also patterns within each type of elements, as each is distributed according to their similar characteristics. For example, the noble gases can be found in group 8A (which is eight columns over from the left), and the noble gas family are all odorless, colorless, and do not have the desire to chemically react with other elements. Other important groups to remember are alkali metals in group 1A, alkaline earth metals in group 2A, and halogens in group 7A.
What Can You Find on the Periodic Table?
Let’s look at the element rubidium (Rb) to review the types of information you can find on the periodic table:
- The atomic symbol is the abbreviation of the element name.
- The element name is the common name for the element.
- At the top is the atomic number, which represents the number of protons in the atomic nucleus of the element.
It also represents the number of electrons in the electron cloud that circles the atomic nucleus.
- At the bottom, below the element name, you will see the atomic mass. This is a size measurement of the atom.
The trends of the periodic table allow us to discover even more about the properties of an element, as well as how reactive it is with other elements.
Let’s look at a few different periodic trends:Atomic radius is a measurement of the size of the atoms within an element. It usually presents the distance from the nucleus to the outer edge of the electron cloud. (You can also think of it as half the distance between two atoms’ nuclei.
) So what is the trend of atomic radius on the periodic table? Atomic radius increase when you move from right to left across the period table, as well as when you move from top to bottom.
Electronegativity is a property that tells you about the tendency of an atom to attract electrons.
A molecule is formed when two or more atoms bond together. Often, these atoms will share electrons to form that bond. However, this sharing is not always equal.
If you can predict the electronegativity, then you can determine which atoms will share the most electrons, which are downright greedy, and even which will steal electrons from other atoms.As shown in the image below, the trend for electronegativity is the opposite of the atomic radius trend. Electronegativity increases when you move from bottom to top and left to right.
Ionization energy is the amount of energy required to take away an electron from an atom.
Electron affinity is the measure in energy change when an atom gains or loses energy from accepting an extra electron. As they’re closely related to electronegativity, both of these measurements follow the same trend as electronegativity–ionization energy and electron affinity increase from bottom to top and left to right.
Now that we’ve covered trends of the periodic table, there is one disclaimer to point out: There are exceptions. For example, noble gases and transition metals have small differences in their electronegativity values, so you may not be able to predict their electronegativity, ionization energy, and electron affinity according to the trends.
The periodic table can be used to learn about the properties of an element, such as atomic atomic symbol, element name, atomic number, and atomic mass. You can also find trends in the periodic table that allow you to predict an elements atomic radius, electronegativity, ionization energy, and electron affinity.
Remember this: When you move from right to left and top to bottom, atomic radius increases. When you move in the opposite direction–from bottom to top and left to right, electronegativity, ionization energy, and electron affinity all increase.