The number of acyclic structural isomers (including geometrical isomers) for pentene are ___________

Assume a cell with the following reaction

$$C{u_{(s)}} + 2A{g^ + }(1 \times {10^{ - 3}}M) \to C{u^{2 + }}(0.250M) + 2A{g_{(s)}}$$

$$E_{cell}^\Theta = 2.97$$ V

E_cell for the above reaction is ______________ V. (Nearest integer)

[Given : log 2.5 = 0.3979, T = 298 K]

Value of K_P for the equilibrium reaction

N₂O_4(g) $$\rightleftharpoons$$ 2NO_2(g) at 288 K is 47.9. The K_C for this reaction at same temperature is ____________. (Nearest integer)

(R = 0.083 L bar K^$$-$$1 mol^$$-$$1)

If the standard molar enthalpy change for combustion of graphite powder is $$-$$2.48 $$\times$$ 10² kJ mol^$$-$$1, the amount of heat generated on combustion of 1 g of graphite powder is ___________ kJ. (Nearest integer)