Question

In lab you measure out \[87.25{\text{ }}g\]of \[{C_4}{H_8}{O_4}\] for an experiment. How many mol is this?

Answer 1

Hint:As we know that, \[1\]mole of any atom or molecule or ion contains Avogadro’s number (\[{N_A}\] ) of molecule
So, \[1\,mole\, = \,6.022\, \times \,{10^{23}}\,atoms\]
Therefore, for \[1\] molecule will be;
\[1\,\,atoms\, = \,\dfrac{1}{{6.022\, \times \,{{10}^{23}}}}\,moles\]
So, the answer will be;
\[1\,atoms\, = 1.66\, \times \,{10^{ - 24}}\,moles\]

Complete step-by-step answer: First, we need to calculate the number of moles of \[{C_4}{H_8}{O_4}\];
As we know that, the number of moles will be equal to the given mass divided by the molecular mass a compound.
Hence, the formula will be as follows,
\[n\,\, = \,\,\dfrac{{mass}}{{molar\,mass}}\]
Where,
\[n\, = \] the amount in moles \[(mol)\]
Mass will be in the terms of\[\;(g)\]
Molar mass will be in the terms of \[\;(g/mol)\]
So, we need to calculate the moles of \[{C_4}{H_8}{O_4}\] .
first, we need to calculate the molar mass of \[{C_4}{H_8}{O_4}\]and then we need to calculate the moles.
Let’s calculate the molar mass of this compound \[{C_4}{H_8}{O_4}\];
The molar mass of carbon \[ = \,12\,g/mol\]
We have four carbons so the overall molar mass for carbon will be;
 \[ = \,12\, \times \,4\, = \,48\,g/mol\]
The molar mass of hydrogen \[ = \,1.0\,g/mol\]
We have eight hydrogens so the overall molar mass for hydrogen will be;
 \[ = \,1\, \times \,8\, = \,8\,g/mol\]
The molar mass of oxygen \[ = \,16\,g/mol\]
We have four oxygen so the overall molar mass for oxygen will be;
 \[ = \,16\, \times \,4\, = \,64\,g/mol\]
Now the total molar mass of \[{C_4}{H_8}{O_4}\] will be;
\[ = \,48\, + \,8\, + 64\]
\[ = \,120\,g/mol\]
Now, the given mass of\[{C_4}{H_8}{O_4}\]\[ = \,87.25{\text{ }}g\]
Let’s substitute in the values;
\[n\,\, = \,\,\dfrac{{\,87.25\,g}}{{120\,g/mol}}\,\]
\[ = \,0.727\,moles\]
So, for the \[87.25{\text{ }}g\] of \[{C_4}{H_8}{O_4}\]is \[0.727\,moles\]

Note:A mole is a unit measurement for the amount of substance in the international system of units i.e., SI unit. A mole of a particle or a mole of a substance is defined as \[6.02214076 \times {10^{23}}\] of a chemical unit, that can be ions, atoms, molecules, etc. Originally it was defined as, the number of atoms in \[12{\text{ }}g\] of carbon-12.