How the they get mass and mole

The mass of potassium hydrogen phthalate (KHP) was obtained by weighing it directly using a balance. This is a standard procedure for preparing a primary standard solution.

The moles of KHP were then calculated using the measured mass of KHP and its molar mass. The molar mass of KHP (chemical formula $\text{KC}_8\text{H}_5\text{O}_4$) is $204.24 \text{ g/mol}$.

The formula used for calculating moles is:

$$\text{Moles} = \frac{\text{Mass (g)}}{\text{Molar Mass (g/mol)}}$$

For example, in Trial 1:

• Mass of KHP: $0.21900 \text{ g}$
• Molar Mass of KHP: $204.24 \text{ g/mol}$

$$\text{Moles of KHP (Trial 1)} = \frac{0.21900 \text{ g}}{204.24 \text{ g/mol}} = \boxed{0.00107 \text{ mol}}$$