Chemistry

The oxidation states of transition metal atoms in K₂Cr₂O₇, KMnO₄ and K₂FeO₄, respectively, are x,y and z. The sum of x,y and z is [numerical value].

The work function of sodium metal is 4.41 * 10⁻¹⁹ J. If photons of wavelength 300 nm are incident on the metal, the kinetics energy of the ejected electrons will be (h = 6.63 * 10⁻³⁴ Js; c = 3 * 10⁸ m/s) * 10⁻²¹ J. [numerical value].

The heat of combustion of ethanol into carbon dioxides and water is –327kcal at constant pressure. The heat evolved (in cal) at constant volume at 27°C (if all gases behave ideally) is (R=2calmol⁻¹K⁻¹) [numerical value].

For the disproportionation reaction 2Cu⁺(aq) ⇌ Cu(s) + Cu²⁺ at 298 K, ln K (where K is the equilibrium constant) is * 10⁻¹.
Given: (E⁰(Cu²⁺/Cu⁺) = 0.16V, E⁰(Cu⁺/Cu) = 0.52V, RT/F = 0.025) [numerical value].

The ratio of the mass percentages of 'C&H' and 'C&O' of a saturated acyclic organic compound 'X' are 4:1 and 3:4 respectively. Then, the moles of oxygen gas required for complete combustion of two moles of organic compound 'X' is [numerical value].

The ratio of the mass percentages of 'C&H' and 'C&O' of a saturated acyclic organic compound 'X' are 4:1 and 3:4 respectively. Then, the moles of oxygen gas required for complete combustion of two moles of organic compound 'X' is [numerical value].

The molecular geometry of SF₆ is octahedral. What is the geometry of SF₄ (including lone pair(s) of electrons, if any)?