What is the molecular mass of potassium hydrogen carbonate (KHCO3)?
A. 110g/mol
B. 84g/mol
C. 68g/mol
D. 116g/mol
You can't add these up? Look on your periodic table and add the atomic masses.
To find the molecular mass of potassium hydrogen carbonate (KHCO3), we need to calculate the sum of the atomic masses of all the atoms in the compound.
The atomic masses of the elements involved are:
- Atomic mass of potassium (K) = 39.10 g/mol
- Atomic mass of hydrogen (H) = 1.01 g/mol
- Atomic mass of carbon (C) = 12.01 g/mol
- Atomic mass of oxygen (O) = 16.00 g/mol
In KHCO3, there is 1 potassium (K), 1 hydrogen (H), 1 carbon (C), and 3 oxygen (O) atoms.
Now, let's calculate the molecular mass:
Molecular mass = (1 * atomic mass of K) + (1 * atomic mass of H) + (1 * atomic mass of C) + (3 * atomic mass of O)
= (1 * 39.10 g/mol) + (1 * 1.01 g/mol) + (1 * 12.01 g/mol) + (3 * 16.00 g/mol)
= 39.10 g/mol + 1.01 g/mol + 12.01 g/mol + 48.00 g/mol
= 100.12 g/mol
So, the molecular mass of potassium hydrogen carbonate (KHCO3) is 100.12 g/mol. None of the given options match this value, so it seems that there might be a mistake in the answer choices.