Two identical 19.2 g copper samples were taken. The first was completely dissolved in excess concentrated nitric acid, the second in excess dilute nitric acid. The salt from the second experiment was isolated and heated to constant mass, and the evolved gases were completely absorbed in 200 g of water. 1) Balance both reactions by electron balance and calculate the gas volume (L, STP) evolved in each experiment. 2) Determine the mass of nitric acid consumed in each experiment and what part of it acted as the oxidant. 3) Write the thermal decomposition of copper(II) nitrate, find the mass of the solid residue and calculate the mass fraction (%) of acid in the solution formed when the gases were absorbed. For every part, show the method (reaction equations, formulas, reasoning) and all calculations step by step.
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