The formula to calculate the Mass Error (ppm) is:
\[ \text{Mass Error (ppm)} = \left( \frac{\text{Experimental Mass} - \text{Theoretical Mass}}{\text{Theoretical Mass}} \right) \times 10^6 \]
Where:
Mass error is a measure of the accuracy of a mass spectrometry measurement. It quantifies the difference between the measured mass of an ion and its calculated theoretical mass based on its elemental composition. Mass error is typically expressed in parts per million (ppm) to provide a unit that is independent of the ion's mass, allowing for comparison across different mass ranges.
Let's assume the following values:
Step 1: Calculate the difference between experimental mass and theoretical mass:
\[ 1001 - 1000 = 1 \]
Step 2: Divide the difference by the theoretical mass:
\[ \frac{1}{1000} = 0.001 \]
Step 3: Multiply by one million to convert to ppm:
\[ 0.001 \times 10^6 = 1000 \text{ ppm} \]
The Mass Error is 1000 ppm.