How Many Cl Atoms Are in 0.0728 g of PCl3?
Chemistry is often seen as a complex and intimidating subject, but understanding the fundamentals can make it much simpler. In this article, we will explore a common question that often arises in chemistry calculations: how many Cl atoms are in a given amount of PCl3?
Before we dive into the calculation, let’s first understand the chemical formula of PCl3. PCl3 stands for phosphorus trichloride, which is a compound composed of one phosphorus (P) atom and three chlorine (Cl) atoms.
To determine the number of Cl atoms in a given amount of PCl3, we need to use the concept of molar mass. Molar mass is the mass of one mole of a substance and is expressed in grams per mole (g/mol). The molar mass of PCl3 can be calculated by adding up the atomic masses of phosphorus and chlorine.
The atomic mass of phosphorus is approximately 31.0 g/mol, while the atomic mass of chlorine is about 35.5 g/mol. Therefore, the molar mass of PCl3 is:
Molar mass of PCl3 = (1 × atomic mass of P) + (3 × atomic mass of Cl)
= (1 × 31.0 g/mol) + (3 × 35.5 g/mol)
= 31.0 g/mol + 106.5 g/mol
= 137.5 g/mol
Now, armed with the molar mass of PCl3, we can proceed to solve the question. We are given that we have 0.0728 g of PCl3. To determine the number of Cl atoms, we need to convert grams to moles and then use the Avogadro’s number, which represents the number of entities (atoms, molecules) in one mole of a substance.
Using the equation:
Number of moles = Mass of substance (g) / Molar mass (g/mol)
We can calculate the number of moles of PCl3:
Number of moles of PCl3 = 0.0728 g / 137.5 g/mol ≈ 0.000530 mol
Now that we know the number of moles of PCl3, we can use Avogadro’s number to find the number of Cl atoms. Avogadro’s number is approximately 6.022 × 10^23 entities/mol.
Number of Cl atoms = Number of moles × Avogadro’s number
Number of Cl atoms = 0.000530 mol × 6.022 × 10^23 atoms/mol ≈ 3.19 × 10^20 atoms
To summarize, in 0.0728 g of PCl3, there are approximately 3.19 × 10^20 Cl atoms. This calculation allows us to determine the number of Cl atoms in any given amount of PCl3 by utilizing the molar mass, Avogadro’s number, and basic stoichiometry principles.
Understanding calculations like these is crucial for scientists, as it enables them to determine the quantities of various substances involved in chemical reactions and understand the properties of different compounds. It also helps in optimizing industrial processes and designing experiments in a controlled manner.
Remember, chemistry is all about breaking down complex problems into simple steps and utilizing basic principles to solve them. By mastering these calculations, you can gain a deeper understanding of the world of atoms and molecules.
In conclusion, the answer to the question “How many Cl atoms are in 0.0728 g of PCl3?” is approximately 3.19 × 10^20 Cl atoms. Understanding the concepts of molar mass, Avogadro’s number, and stoichiometry helps us unravel the mysteries of chemistry and appreciate its practical applications in our daily lives.