Question

this unbalanced equation represents a chemical reaction: cu(no₃)₂ + nai → nano₃ + cui₂
what is the coefficient for cu(no₃)₂ once the equation is balanced?
1
2
3
4

Explanation:

Step1: Analyze Iodine atoms

On the right, \( \text{CuI}_2 \) has 2 I atoms. On the left, \( \text{NaI} \) has 1 I atom. So \( \text{NaI} \) needs a coefficient of 2.

Step2: Analyze Sodium atoms

After setting \( \text{NaI} \) to 2, left has 2 Na. So \( \text{NaNO}_3 \) needs coefficient 2.

Step3: Analyze Nitrate groups

Left \( \text{Cu(NO}_3\text{)}_2 \) has 2 nitrate, right \( \text{NaNO}_3 \) (2) has 2 nitrate. Copper: left \( \text{Cu(NO}_3\text{)}_2 \) has 1 Cu, right \( \text{CuI}_2 \) has 1 Cu. So \( \text{Cu(NO}_3\text{)}_2 \) coefficient is 1.
Balanced equation: \( \text{Cu(NO}_3\text{)}_2 + 2\text{NaI}
ightarrow 2\text{NaNO}_3 + \text{CuI}_2 \)

Answer:

1