To determine how many potassium atoms are present in one formula unit of potassium carbonate (K₂CO₃), we need to carefully examine the chemical formula provided:
1. Look at the element symbols in the formula K₂CO₃:
- K represents potassium.
- C represents carbon.
- O represents oxygen.
2. The subscripts after each element indicate the number of atoms of that element in one formula unit of the compound:
- The subscript '2' next to K means there are 2 potassium (K) atoms.
- There is no subscript after C, which implies there is 1 carbon (C) atom.
- The subscript '3' next to O means there are 3 oxygen (O) atoms.
3. Since we are only interested in the potassium atoms, we focus on the subscript next to the potassium (K) element in the formula K₂CO₃.
- The subscript '2' indicates there are exactly 2 potassium atoms in one formula unit of potassium carbonate.
Therefore, the number of potassium atoms in one formula unit of potassium carbonate (K₂CO₃) is 2.
So, the answer is:
B. 2 atoms
