Question

1. 3cu(no)₂ cu= n= o=

Explanation:

Step1: Analyze copper atoms

The coefficient in front of $3Cu(NO)_2$ is 3 and there is 1 Cu atom in each $Cu(NO)_2$ unit. So the number of Cu atoms is $3\times1 = 3$.

Step2: Analyze nitrogen atoms

There is 1 N atom in each $NO$ group and 2 $NO$ groups in each $Cu(NO)_2$ unit, and the coefficient is 3. So the number of N atoms is $3\times2\times1=6$.

Step3: Analyze oxygen atoms

There is 1 O atom in each $NO$ group and 2 $NO$ groups in each $Cu(NO)_2$ unit, and the coefficient is 3. So the number of O atoms is $3\times2\times1 = 6$.

Answer:

$Cu = 3$, $N = 6$, $O = 6$