Solutions to Web Experiment: ICF Table

Web Experiment: Initial-Change-Final Table
Solutions to Problems


  1. Six molecules of C will be formed.


    1. Enter the known values for the initial numbers of A and C molecules and the final numbers of A and B molecules into the IFC table.

    2. The change in the number of A molecules is the difference between the final number of A molecules and the initial number of A molecules. Enter that change in the ICF Table.


    3. Use the appropriate mole ratios to calculate the magnitudes of the changes in the numbers of B and C molecules from the magnitude of change in the number A molecules. The change in the number of B molecules will be a negative number (B is consumed) and the change in the number of C will be a positive number. Enter the changes in the ICF Table.


    4. The initial number of B molecules is equal to the final number of B molecules minus the change in the number of B molecules. The initial number of C molecules plus the change in the number of C molecules is equal to the final number of C molecules.


    5. Allow 10 molecules of A to react with 3 molecules of B and use the ICF Table to verify your calculations.


      6.



  2. Four molecules of A were allowed to react with nine molecules of B.


    1. Enter the known values for the initial number of C molecules and the final numbers of A, B, and C molecules into the IFC table.

    2. The change in the number of C molecules is the difference between the final number of C molecules and the initial number of C molecules. Enter that change in the ICF Table.


    3. Use the appropriate mole ratios to calculate the magnitudes of the changes in the numbers of A and B molecules from the magnitude of change in the number C molecules. Since molecules of A and B are consumed, the changes in the numbers of A and B molecules will be negative numbers. Enter the changes in the ICF Table.


    4. The initial number of A molecules is equal to the final number of A molecules minus the change in the number of A molecules. The initial number of B molecules is equal to the final number of B molecules minus the change in the number of B molecules.


    5. Allow 4 molecules of A to react with 9 molecules of B and use the ICF Table to verify your calculations.


      6.



  3. Ten molecules of C will be formed.


    1. Let x be the final number of C molecules. Since there are three times as many A molecules as B molecules, B is the limiting reactant and the final number of B molecules will be 0. Enter 0 for the initial number of C molecules, 0 for the final number of B molecules, and x for the final numbers of C molecules into the IFC table.


    2. The change in the number of C molecules is the difference between the final number of C molecules and the initial number of C molecules. Enter that change in the ICF Table.


    3. Use the appropriate mole ratios to calculate the magnitudes of the changes in the numbers of A and B molecules from the magnitude of change in the number C molecules. Since molecules of A and B are consumed, the changes in the numbers of A and B molecules will be negative numbers. Enter the changes in the ICF Table.


    4. The initial number of B molecules is equal to the final number of B molecules minus the change in the number of B molecules.


    5. The problem states that initially there are three times as many molecules of A as molecules of B . The initial number of A molecules is then three times the initial number of B molecules. Enter 1.5x for the initial number of molecules of A.


    6. The initial number of A molecules plus the change in the number of A molecules is equal to the final number of A molecules.


    7. x molecules of the 20 molecules in the container at the completion of the reaction are A molecules and x molecules are C molecules. Hence, 10 molecules of C were formed.


    8. Allow 15 molecules of A to react with 5 molecules of B and use the ICF Table to verify your calculations.


      9.