A chemist performed an experiment in which silver nitrate was used to precipitate all of the chromate ion as silver chromate, Ag2CrO4 from 200 mL of a solution of potassium chromate, K2CrO4. This process required 120 mL of 0.200 M AgNO3.
Write the balanced equation that describes this process
AgNO3 + K2CrO4 --> Ag2CrO4 + KNO3
You balance it.
2AgNO3 + K2CrO4 --> Ag2CrO4 + 2KNO3
To write the balanced equation, we need to first identify the ions present in the reactants and products.
Reactants:
- Potassium chromate, K2CrO4: This consists of K+ ions and CrO4^2- ions.
- Silver nitrate, AgNO3: This consists of Ag+ ions and NO3- ions.
Products:
- Silver chromate, Ag2CrO4: This consists of Ag+ ions and CrO4^2- ions.
The balanced equation for the reaction can be written as follows:
2AgNO3 + K2CrO4 → Ag2CrO4 + 2KNO3
Explanation of how to balance the equation:
1. Start by counting the number of atoms of each element on both sides of the equation.
- On the left side, we have 2 Ag atoms, 2 N atoms, 6 O atoms, 2 K atoms, and 1 Cr atom.
- On the right side, we have 2 Ag atoms, 1 Cr atom, 6 O atoms, 2 K atoms, and 2 N atoms.
2. The number of atoms of each element should be equal on both sides of the equation. To balance the equation, adjust the coefficients (numbers in front of the compounds) until the atoms are balanced.
- To balance the Ag atoms, we need a coefficient of 2 in front of AgNO3.
- To balance the N atoms, we need a coefficient of 2 in front of KNO3.
- The O atoms are already balanced.
- The K and Cr atoms are already balanced.
3. After balancing the coefficients, recheck to ensure that all elements are balanced.
The final balanced equation is 2AgNO3 + K2CrO4 → Ag2CrO4 + 2KNO3.