Aspirin (C9H8O4) Molar Mass (With Calculations)

Molar mass of Aspirin (or Acetylsalicylic acid or C9H8O4) is 180.159 g/mol.

Well, now you have come to know the molar mass of Aspirin.

But how can you get this value?

Let me show you the calculation to get the molar mass of Aspirin (or Acetylsalicylic acid or C9H8O4).

If you are a visual learner like me, then here is a short one minute video for you.

Aspirin (C9H8O4) Molar Mass Calculation

If you have a periodic table with you, then you can easily calculate the molar mass of Aspirin (or Acetylsalicylic acid or C9H8O4).

Because the molar mass of any molecule (or compound) can be calculated by simply adding the molar masses of individual atoms.

Now here we have to find the molar mass of Aspirin (C9H8O4).

So for that, have a look at the periodic table given below.

You can see the molar mass value of all the atoms from this periodic table.

Now in Aspirin (C9H8O4), there are 9 Carbon atoms, 8 Hydrogen atoms and 4 Oxygen atoms.

So let’s look at the molar mass of Carbon, Hydrogen and Oxygen from the above periodic table.

You can see that;

The molar mass of Carbon is 12.011 g/mol. ^[1]

The molar mass of Hydrogen is 1.008 g/mol. ^[2]

The molar mass of Oxygen is 15.999 g/mol. ^[3]

Now, to calculate the molar mass of Aspirin, you just have to add the molar mass of all the individual atoms that are present in Aspirin.

You can see that in Aspirin (C9H8O4), there are 9 Carbon atoms, 8 Hydrogen atoms and 4 Oxygen atoms.

So, Molar mass of Aspirin (C9H8O4) = Molar mass of 9 Carbon (C) atoms + Molar mass of 8 Hydrogen (H) atoms + Molar mass of 4 Oxygen (O) atoms.
= (12.011) 9 + (1.008) 8 + (15.999) 4
= 108.099 + 8.064 + 63.996
= 180.159 g/mol

Hence the Molar mass of Aspirin (C9H8O4) is 180.159 g/mol.

I hope you have understood the short and simple calculation for finding the molar mass of Aspirin.

Remember

• In some books, you may see the unit of molar mass as grams/mole or g/mole. But all these units (i.e g/mol, grams/mole and g/mole) are the same. 
• Always follow the calculation order to avoid any mistakes in calculation. First solve the brackets, then multiplications and at last do the final addition.
• And don’t forget to put the unit g/mol to your final calculated molar mass.

Check out other related topics for more practice;
Butane (C4H10) Molar Mass
KNO3 (Potassium nitrate) Molar Mass
C3H8 (Propane) Molar Mass
BaSO4 (Barium sulfate) Molar Mass
Octane (C8H18) Molar Mass