What is the gram formula mass of K2CO3?
Understand the Problem
The question is asking for the gram formula mass of potassium carbonate (K2CO3). To solve this, we will need to calculate the molar mass by summing the atomic masses of all the elements in the formula: K (potassium), C (carbon), and O (oxygen) based on the number of each present in one formula unit of K2CO3.
Answer
$138.21 \, \text{g/mol}$
Answer for screen readers
The gram formula mass of potassium carbonate (K2CO3) is $138.21 , \text{g/mol}$.
Steps to Solve
- Identify the elements and their quantities in K2CO3
In potassium carbonate (K2CO3), we have:
- Potassium (K): 2 atoms
- Carbon (C): 1 atom
- Oxygen (O): 3 atoms
- Find the atomic masses of each element
Using a periodic table, we find the atomic masses:
- Potassium (K): approximately 39.10 g/mol
- Carbon (C): approximately 12.01 g/mol
- Oxygen (O): approximately 16.00 g/mol
- Calculate the total mass for each element in K2CO3
Now we multiply the number of atoms by the atomic mass for each element:
- For Potassium: $$ 2 \times 39.10 , \text{g/mol} = 78.20 , \text{g/mol} $$
- For Carbon: $$ 1 \times 12.01 , \text{g/mol} = 12.01 , \text{g/mol} $$
- For Oxygen: $$ 3 \times 16.00 , \text{g/mol} = 48.00 , \text{g/mol} $$
- Sum up the total mass
Add all the masses calculated: $$ 78.20 , \text{g/mol} + 12.01 , \text{g/mol} + 48.00 , \text{g/mol} = 138.21 , \text{g/mol} $$
The gram formula mass of potassium carbonate (K2CO3) is $138.21 , \text{g/mol}$.
More Information
Potassium carbonate is often used in fertilizers, glass production, and as a food additive. Understanding how to calculate the molar mass is essential in chemistry for stoichiometric calculations.
Tips
- Forgetting to include the correct number of atoms for each element.
- Misremembering the atomic masses of the elements.
- Failing to add up the total mass correctly at the end.
