Fluoxetine, marketed as an antidepressant under the name Prozac, can be represented by the following ball-and-stick molecular model. Write the molecular formula for fluoxetine, and calculate its molecular weight. (Red = O, gray = C, blue = N, yellow green = F, ivory = H.)

Key Concepts

Molecular Formula

The molecular formula of a compound indicates the types and numbers of atoms present in a molecule. It is expressed using chemical symbols, where each element is represented by its symbol followed by a subscript that denotes the number of atoms of that element. For fluoxetine, identifying the correct number of carbon (C), hydrogen (H), nitrogen (N), oxygen (O), and fluorine (F) atoms from the molecular model is essential to write its accurate molecular formula.

Molecular Weight

Molecular weight, or molar mass, is the sum of the atomic weights of all atoms in a molecule, measured in grams per mole (g/mol). To calculate the molecular weight of fluoxetine, one must multiply the number of each type of atom in the molecular formula by its respective atomic weight (found on the periodic table) and then sum these values. This calculation provides insight into the mass of one mole of the substance, which is crucial for stoichiometric calculations in chemistry.

Ball-and-Stick Model

A ball-and-stick model is a three-dimensional representation of a molecule that illustrates the arrangement of atoms and the bonds between them. In this model, balls represent atoms, while sticks represent the bonds connecting them. Understanding this model helps in visualizing the molecular structure of fluoxetine, allowing for the identification of the different atoms and their connectivity, which is vital for determining the molecular formula and calculating molecular weight.