Question

Given that the only naturally occurring isotope of fluorine is \({ }^{19} \mathrm{~F}\), determine its mass from the periodic table.

Short answer

The mass of fluorine from the periodic table is approximately 19 u (atomic mass units), matching ^{19} F.

Step-by-step solution

Access the Periodic Table

To determine the mass of the isotope ^{19} F, first access a periodic table. This can be in the form of a print resource or an online database. The periodic table contains information about all the elements and their properties.

Locate Fluorine

Find the element fluorine on the periodic table. It is usually listed with the symbol 'F' and is positioned in group 17 (halogens), period 2.

Note the Atomic Mass

Once you locate fluorine, look for the number beneath its symbol 'F'. This number represents the atomic mass of fluorine, which accounts for the average mass of all naturally occurring isotopes. For fluorine, in its natural form, this is primarily ^{19} F.

Confirm the Mass of ^{19} F

The atomic mass number found on the periodic table for fluorine should closely match the mass number of ^{19} F, since ^{19} F is the only stable, naturally occurring isotope of fluorine.

Key concepts

Periodic Table

The periodic table is a comprehensive chart used by chemists and scientists to organize elements based on their chemical properties. Each element is placed in order of increasing atomic number, which represents the number of protons in an atom's nucleus. This table is like a map for all the known chemical elements.

When you use a periodic table, you'll notice that it is arranged into groups and periods. The groups are the vertical columns, and these indicate elements with similar characteristics. This is crucial for chemists who want to predict the reactions and behavior of different elements.

One special aspect of the periodic table is that it consolidates a lot of information. For each element, you can typically find its symbol (like 'F' for fluorine), atomic number, and atomic mass. These values allow you to understand more about the element's properties, such as its isotopes and the number of electrons it has.

Atomic Mass

Atomic mass is an essential concept that gives insight into the weight of an element's atoms. It is calculated as a weighted average of all the naturally occurring isotopes of that element. This means that the atomic mass reflects the masses of each isotope and their respective abundance.

For fluorine, the atomic mass you see on the periodic table considers its isotopes. However, since fluorine is unique in having only one stable isotope, ^{19}F, its atomic mass is very close to 19. This simplifies calculations for chemists, as they can reliably use this mass when working with fluorine in chemical reactions or calculations.

If an element had multiple isotopes, the atomic mass would be a more complex calculation, reflecting the different isotopic masses weighted by their abundance. But, in the case of fluorine, having a sole isotope makes it straightforward.

Group 17 Elements

Fluorine is a member of the group 17 elements on the periodic table. This group is famously known as the halogens. Other members of this group include chlorine (Cl), bromine (Br), iodine (I), and astatine (At).

Halogens are known for being highly reactive, particularly with elements in group 1, the alkali metals. This reactivity is due to the halogens' need to gain an electron to achieve a stable electron configuration, making them very eager to form compounds in nature.

Because of their high reactivity, halogens are often found in nature as compounds rather than in their pure form. Fluorine, for instance, readily forms bonds, contributing to the commonness of compounds like fluoride in various minerals and household products.