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,
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You can find the molar mass of aluminum in a periodic table and substitute it into the mole formula along with the given mass.
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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
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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:
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Apply the mole formula and round-off the answer:
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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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