Understanding Moles and Atomic Mass

The question asks us to find the number of moles of Sulphur given its mass and atomic mass. To solve this, we need to understand the relationship between mass, atomic mass, and the concept of a mole.

What is Atomic Mass?

Atomic mass is the mass of an atom. It is often expressed in atomic mass units (u). For Sulphur, the atomic mass is given as 32 u.

What is Molar Mass?

Molar mass is the mass of one mole of a substance. For elements, the molar mass in grams per mole (g/mol) is numerically equal to the atomic mass in atomic mass units (u). So, the molar mass of Sulphur is 32 g/mol.

What is a Mole?

A mole is a unit used to measure the amount of substance. One mole of any substance contains Avogadro's number ($\text{6.022} \times \text{10}^\text{23}$) of particles (atoms, molecules, ions, etc.).

Calculating Moles of Sulphur

We can calculate the number of moles using the following formula:

$\text{Number of moles} = \frac{\text{Mass of substance}}{\text{Molar mass of substance}}$

Let's apply this formula to the given problem:

• Given mass of Sulphur = 16 grams
• Atomic mass of Sulphur = 32 u
• Molar mass of Sulphur = 32 g/mol

Now, we plug these values into the formula:

$\text{Number of moles of Sulphur} = \frac{\text{16 g}}{\text{32 g/mol}}$

Let's perform the calculation:

$\text{Number of moles of Sulphur} = \text{0.5 mol}$

Result and Options Analysis

The calculation shows that 16 grams of Sulphur corresponds to 0.5 moles of Sulphur.

Let's compare this with the given options:

• Option 1: 0.5 moles of Sulphur
• Option 2: 0.25 moles of Sulphur
• Option 3: 0.75 moles of Sulphur
• Option 4: 1 mole of Sulphur

Our calculated value matches Option 1.

Revision Table: Key Concepts

Additional Information: The Mole Concept in Chemistry

The mole concept is fundamental in chemistry because it allows us to relate the mass of a substance to the number of particles (atoms, molecules) it contains. This is crucial for understanding chemical reactions, stoichiometry, and preparing solutions of specific concentrations.

• One mole of any element contains Avogadro's number of atoms.
• One mole of any compound contains Avogadro's number of molecules.
• The molar mass of a compound is the sum of the atomic masses of all atoms in its chemical formula, expressed in g/mol. For example, the molar mass of water ($\text{H}_\text{2}\text{O}$) is approximately $(2 \times \text{1.008}) + \text{15.999} = \text{18.015 g/mol}$.