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Daily Dose 043 | Chemistry
How to find the Mass Fraction?


Mass Fraction.
For most, this, amongst anything else Chemistry, isn’t a topic we easily accept as necessary knowledge in the world of engineering.
After all, we are trying to become Professional Engineers – not professional chemists, but…
We as engineers must understand the relationships between the structures and the properties of substances when specifying the materials within our designs.
Failing to do so can only increase the risks of catastrophic failure.
In this video, we dive into an FE Exam Practice Problem in the subject of CHEMISTRY, showing you how to quickly and efficiently solve these types of problems.
Key Definition
What is a MASS FRACTION?
A MASS FRACTION is a ratio that represents the mass of a particular substance in relation to the total mass of the mixture as a whole.
It can also be expressed, with a denominator of 100, as a percentage by mass (in commercial contexts often called percentage by weight, abbreviated wt%). It is one way of expressing the composition of a mixture in a dimensionless size, others being the MOLE FRACTION and the VOLUME FRACTION.
The Process
So how can we find the Mass Fraction?
Chemistry tends to present itself much more difficult than it actually is. In fact, most all problem types can be broken down into a general step by step process.
To find the Mass Fraction you can follow these general steps:
- Understand the problem
- Determine the relevant masses
- Calculate the total mass
- Calculate the Mass Fraction
- Express the mass fraction
- Check the units and significant figures
Read the problem carefully and make sure you understand what is being asked. Identify the substances involved and any specific information provided.
Identify the masses of the substances or components for which you need to calculate the mass fraction. If the masses are not directly given, you may need to use other information such as molar masses or stoichiometry to determine the masses.
Determine the total mass of the system or mixture. This can be done by summing up the masses of all the components involved.
The mass fraction of a component is the ratio of the mass of that component to the total mass of the system.
With all the appropriate data defined, use the formula:
Mass fraction = (Mass of component) / (Total mass)
Mass fraction is typically expressed as a decimal or a percentage. Depending on the problem or the requested format, convert the result to the appropriate form.
Ensure that your calculations are consistent with the given units and any required significant figures. Round off the final answer as needed.
Check out the video and see how we can go about solving this type of problem in the most efficient manner.
We are here to help.
As always, with Love, Prepineer
Video Review
[VIDEO] How to find the Mass Fraction
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