Final answer:
To balance the decomposition of copper (II) nitrate, coefficients were systematically assigned to create an equation with the same number of each atom on both sides resulting in the balanced equation: 2 Cu(NO3)2 → 2 CuO + 4 NO2 + O2.
Step-by-step explanation:
To balance the given chemical equation for the decomposition of copper (II) nitrate, you must ensure that the number of atoms of each element is the same on both sides of the equation. Let's denote the unknown coefficients as n, o, p, and q, respectively.
The unbalanced chemical equation is:
n Cu(NO₃)₂ → o CuO + p NO₂ + q O₂
Through the process of balancing, we assign coefficients to the reactants and products:
- Balance copper (Cu) atoms first: there is one Cu on the left, ensuring there is one Cu on the right.
- Balance nitrogen (N) and oxygen (O) atoms in the nitrate (NO₃)⁻¹ ions: for every one Cu(NO₃)₂, there are two NO₃⁻¹ ions, meaning two nitrogen atoms and six oxygen atoms.
- Balance the nitrogen atoms by ensuring the number of NO₂ molecules results in an equal number of nitrogen atoms on both sides.
- Finally, balance the oxygen atoms by adjusting the coefficients, keeping in mind that O₂ is diatomic. Also note that oxygen in CuO must be accounted for.
After balancing, we have:
2 Cu(NO₃)₂ → 2 CuO + 4 NO₂ + O₂
The coefficients n=2, o=2, p=4, and q=1 yield the balanced equation.
This is achieved by balancing not just the number of atoms but also the charge on both sides of the equation.