Balance Cl₂ + KI → KCl + I₂
Cl₂(g) + 2 KI(aq) → 2 KCl(aq) + I₂(aq)
Balance an equation
Cl₂(g)+2KI(aq)→2KCl(aq)+I₂(aq)
Balanced
Atoms on each side
| Atom | As writtenleft : right | Balancedleft : right |
|---|---|---|
| Cl | 2:1 | 2:2 |
| K | 1:1 | 2:2 |
| I | 1:2 | 2:2 |
Check atoms
How to balance it, step by step
- Count the atoms of each element on both sides, as written.
- Start with the biggest formula, Cl₂: put 1 in front of it.
- Cl: 2 on the left. Put 2 in front of KCl.
- K: 2 on the right. Put 2 in front of KI.
- I: 2 on the left. Put 1 in front of I₂ (1 × 2 = 2).
- Check: Cl 2 = 2, K 2 = 2, I 2 = 2. Balanced.
What happens
It is a displacement reaction: a more reactive element pushes a less reactive one out of its compound. Chlorine is more reactive than iodine, so it displaces iodine from potassium iodide and the solution turns brown.
Chlorine and potassium iodide: quick answers
What is the balanced equation for chlorine and potassium iodide?
Cl₂(g) + 2 KI(aq) → 2 KCl(aq) + I₂(aq). The coefficients are 1, 2, 2 and 1. Each side then has 2 Cl, 2 K and 2 I.
What type of reaction is chlorine and potassium iodide?
It is a displacement reaction: a more reactive element pushes a less reactive one out of its compound. Chlorine is more reactive than iodine, so it displaces iodine from potassium iodide and the solution turns brown.
How do you balance Cl₂ + KI → KCl + I₂?
Start with the biggest formula, Cl₂: put 1 in front of it. Cl: 2 on the left. Put 2 in front of KCl. K: 2 on the right. Put 2 in front of KI. I: 2 on the left. Put 1 in front of I₂ (1 × 2 = 2). Never change a subscript, because that would change the substance.