Most of the naturally occurring processes are spontaneous. a) Give the criteria for spontaneity of a process in terms of free energy change ( DeltaG ) b) Exothermic reactions associated with a decrease in entropy are sponaneous at lower temperatures. Justify on the basis of Gibbs equation. c) Find the temperature above which the reactin MgO_((s))+C_((s))rightarrow Mg_((s))+CO_((g)) becomes spontaneous. (Given ( Delta_rH^theta=490kJmol^-1 & Delta_rS^theta=198JK mol^-1 )

Given the following data: Determine at what temperature the following reaction is spontaneous? Fe O (s) + C (Graphite) to Fe (s) + CO (g)

Free energy, G=- TS, is a state funtion that indicates whether a reaction is spontaneous or non-spontaneous if you think of TS as the part of the system's energy that is discordered already, then (H-TS) is the part of system's energy that is still orderd and therefore free to cause spontaneous change by becoming disorder Also, Delta G = Delta H - T Delta S Form the second law of thermodyamics, a reaction is spontaneous if Delta _("total") S is + ve, nonspontaneous if Delta _("total")S is negative and at equilibrium if Delta_(total)S is zero. Since, - T Delta S= Delta C and since Delta G and Delta S have oposite single we can restate the themodynmaic creation for the spontaneity of a reaction oout at constant temperature and pressure. If Delta G lt 0, the reaction is spontaneous. If Delta G gt 0, the reaction is non-spontaneous. If Delta G =0, the reaction is at equilibrium. Which of the following is trur for the reaction ? H _(2) O (1) hArr H _(2) O (g) at 100^(@) C and 1 atmosphere

Free energy, G=- TS, is a state funtion that indicates whether a reaction is spontaneous or non-spontaneous if you think of TS as the part of the system's energy that is discordered already, then (H-TS) is the part of system's energy that is still orderd and therefore free to cause spontaneous change by becoming disorder Also, Delta G = Delta H - T Delta S Form the second law of thermodyamics, a reaction is spontaneous if Delta _("total") S is + ve, nonspontaneous if Delta _("total")S is negative and at equilibrium if Delta_(lot)S is zero. Since, - T Delta S= Delta C and since Delta G and Delta S have oposite single we can restate the themodynmaic creation for the spontaneity of a reaction oout at constant temperature and pressure. If Delta G lt 0, the reaction is spontaneous. If Delta G gt 0, the reaction is non-spontaneous. If Delta G =0, the reaction is at equilibrium. A particular reaction ha a negative value for the free enregy charge. Then at ordinary temmperature

For the reaction 2A+B rarr C at 298 K, DeltaH=400kJ mol^-1 and DeltaS=0.2 kJk^-1mol^_1 . At what temperature will be reaction become spontaneous considering DeltaH and DeltaS to be constant over the temperature range.

Calculate the pressure of CO_(2) gas at 700 K in the heterogeneous equilibrium reaction CaCO_(3)(s) hArr CaO(s) + 2CO_(2)(g) if Delta G^(@) for the reaction is 130.2 kJ mol^(-1) .

Assertion : If both Delta H ^(@) and Delta S ^(@) are positive then reaction will be spontaneous at high temperature. Reason : All processes with positive entropy change are spontaneous.