Question

Question 38
Look at the following equation.

Fe + Cl2 → FeCl3

In order to follow the law of conservation of mass, this equation must have which set of coefficients, in order from left to right?

Answer 1

To balance the equation \( \text{Fe} + \text{Cl}_2 \rightarrow \text{FeCl}_3 \) according to the law of conservation of mass, we need to ensure that the number of atoms for each element is the same on both sides of the equation.

1. On the right-hand side (products), we have:
- 1 Iron (Fe) atom (from FeCl3)
- 3 Chlorine (Cl) atoms (from FeCl3)

2. On the left-hand side (reactants), we currently have:
- 1 Iron (Fe) atom
- 2 Chlorine (Cl) atoms (from Cl2)

To balance the chlorine atoms, we note that we have 3 chlorine atoms in the product. Therefore, we need to have \(\frac{3}{2}\) (or 1.5) Cl2 molecules to provide 3 Cl atoms:

So the unbalanced equation would look like this:
\[ 2 \text{Fe} + 3 \text{Cl}_2 \rightarrow 2 \text{FeCl}_3 \]

This means we need:
- 2 Fe
- 3 Cl2
- 2 FeCl3

Thus, the coefficients in order from left to right are **2, 3, 2**.

Overall, the balanced equation is:
\[ 2 \text{Fe} + 3 \text{Cl}_2 \rightarrow 2 \text{FeCl}_3 \]

So the answer is **2, 3, 2**.