use the references to access important value. calculate the percentage composition for n₂o₄. mass percentage…

Explanation:

Step1: Determine atomic masses

Atomic mass of N = 14 g/mol, atomic mass of O = 16 g/mol.

Step2: Calculate molar - mass of N₂O₄

Molar - mass of N₂O₄ ($M$) = 2×14 + 4×16 = 28+64 = 92 g/mol.

Step3: Calculate mass percentage of nitrogen

Mass percentage of N = $\frac{2\times14}{92}\times100%=\frac{28}{92}\times100%\approx30.43%$.

Step4: Calculate mass percentage of oxygen

Mass percentage of O = $\frac{4\times16}{92}\times100%=\frac{64}{92}\times100%\approx69.57%$.

Answer:

Mass percentage of nitrogen = 30.43% Mass percentage of oxygen = 69.57%