The rate constants for decomposition of acetaldehyde have been measured over the temperature range 700 - 1000 K. The data has been analysed by plotting ln k vs $${{{{10}^3}} \over T}$$ graph. The value of activation energy for the reaction is ___________ kJ mol^$$-$$1. (Nearest integer)

(Given : R = 8.31 J K^$$-$$1 mol^$$-$$1)

The difference in oxidation state of chromium in chromate and dichromate salts is ___________.

In the cobalt-carbonyl complex : [Co₂(CO)₈], number of Co-Co bonds is "X" and terminal CO ligands is "Y". X + Y = ___________.

A 0.166 g sample of an organic compound was digested with conc. H₂SO₄ and then distilled with NaOH. The ammonia gas evolved was passed through 50.0 mL of 0.5 N H₂SO₄. The used acid required 30.0 mL of 0.25 N NaOH for complete neutralization. The mass percentage of nitrogen in the organic compound is ____________.