chemistry! -converting mass to mole


Mass to Mole Conversions

The mass of a substance can be found using a balance. If you know the molar mass of the substance, then you can convert the mass to a mole amount. Here's an example...

Let's say you want to determine the number of moles in a 56.83 g piece of aluminum.
To solve this problem, you can apply a simple formula, , where n is the number of moles, m is the mass, and M is the molar mass.
You can find the molar mass of aluminum in a periodic table and substitute it into the mole formula along with the given mass.






converting given mass to moles

Example 1

Diamonds are pure carbon. Calculate the number of moles of carbon atoms in a 1.52 g diamond.

Answer :

List the given mass:
m = 1.52 g


Look up the molar mass of carbon:
M = 12.01 g/mol


Apply the mole formula to calculate the number of moles of carbon:
n = ? mol




Communicate the answer:

A 1.52 g diamond contains 0.127 mol of carbon atoms.



Example 2


Calculate the number of moles in a 48.12 g sample of cerium nitrate, Ce(NO3)3?


Answer :

List the given mass:


m = 48.12 g


Calculate the molar mass of cerium nitrate:







Apply the mole formula and round-off the answer:




Communicate the answer:

The number of moles in the sample is 0.1475 mol.

p/s: sbrang teguran membantu.terutamanya dri muallim chemi kita..~^^

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