Ionic Reaction Builder

How to use Ionic Reaction Builder

Predict the products first, then balance the equation. Here is a double replacement example.

  1. Choose your practice. Select at least one reaction type, then choose Start practice.
  2. Build the products. For CuSO4 + Na3PO4, pair Cu2+ with PO43−. Use the subscript arrows to set 3 copper ions and 2 phosphate ions, making Cu3(PO4)2. Pair Na+ with SO42− and set 2 sodium ions to make Na2SO4. Leave a subscript blank for 1.
  3. Check your products. Drag blocks into the spaces, or select a block and then its space. Either product order is accepted. Check products opens balancing when the formulas are correct.
  4. Balance with coefficients. Set the coefficients to 3, 2, 1 and 3 in the order shown below. Keep the subscripts fixed. The live table shows a green check when the counts on the two sides are equal. The green Balanced confirmation appears automatically at the smallest whole-number ratio, and Next reaction becomes available.

Products predicted

CuSO4 + Na3PO4 → Cu3(PO4)2 + Na2SO4

Balanced equation

3CuSO4 + 2Na3PO4 → Cu3(PO4)2 + 3Na2SO4

Check balance gives feedback whenever you need it. Skip problem advances without finishing it. The summary reviews missed and skipped problems; a problem counts only once.

Choose your practice

What would you like to work on?

Choose at least one reaction type. You can include all four in your round.

Choose reaction types

About this activity

Predict the products of synthesis, decomposition, single replacement and double replacement reactions. Write correct ionic formulas, then balance each equation.

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