Understanding Percent Change in Mass
Mass is a fundamental physical property of matter, representing the amount of matter contained within an object. Percent change in mass refers to the change in the mass of an object expressed as a percentage of its original mass. It is a useful metric for quantifying changes in mass and comparing the masses of different objects.

Formula for Calculating Percent Change in Mass
The percent change in mass is calculated using the following formula:
Percent Change in Mass = [(New Mass - Original Mass) / Original Mass] x 100%
Where:
- New Mass is the final mass of the object after the change
- Original Mass is the initial mass of the object before the change
Step-by-Step Approach to Finding Percent Change in Mass
Step 1: Determine the Initial and Final Masses
Identify the original mass (before the change) and the new mass (after the change) of the object. These values must be expressed in the same units (e.g., grams, pounds, kilograms).
Step 2: Calculate the Change in Mass
Subtract the original mass from the new mass to find the change in mass:
Change in Mass = New Mass - Original Mass
Step 3: Calculate the Percent Change in Mass
Substitute the change in mass into the formula for percent change in mass:
Percent Change in Mass = [(Change in Mass / Original Mass) x 100]%
Significance and Applications of Percent Change in Mass
Percent change in mass has numerous applications in various fields:
- Chemistry: Determining the mass lost or gained during chemical reactions
- Physics: Analyzing the mass changes associated with energy transformation (e.g., combustion, nuclear reactions)
- Engineering: Calculating the mass changes in materials due to deformation or processing
- Manufacturing: Monitoring the mass of products during production to ensure quality control
- Environmental Science: Measuring the mass of pollutants or contaminants in environmental samples
Case Studies
To illustrate the calculation of percent change in mass, consider the following case studies:
Case 1: Weight Loss
A person initially weighs 180 pounds and loses 20 pounds through diet and exercise. The percent change in mass is:
Percent Change in Mass = [(180 lbs - 160 lbs) / 180 lbs] x 100% = **-11.11%**
Case 2: Chemical Reaction
In a chemical reaction, 100 grams of a reactant is converted into 120 grams of a product. The percent change in mass is:
Percent Change in Mass = [(120 g - 100 g) / 100 g] x 100% = **+20%**
Additional Resources
Conclusion
Percent change in mass is a valuable tool for quantifying changes in mass and comparing the masses of different objects. By understanding its formula and following a step-by-step approach, you can accurately calculate the percent change in mass for various applications across multiple disciplines.