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Mistake Master · AP Chemistry · Unit 1 · Step-Through Animation

Who Decided the Two

You'll learnhow electron transfer sets each ion's charge and why that fixes the formula.

A magnesium atom and two chlorine atoms always give MgCl2, and the two is not there because you happened to put two chlorines in. Watch the electrons change owner, count what is left on each atom, and the subscript writes itself. Twelve short steps; press Next for each one.

12 STEPS · 6 QUICK CHECKS · MAIN-GROUP IONS · v3

who gives · who takes · what the charges force
Before you start
What you're looking at
One magnesium atom and two chlorine atoms, all neutral, and an empty panel for what they become.
The question
What happens to the electrons, and why exactly two chlorines?
Step 1 / 12