Define enthalpy. Show that the change in enthalpy at constant pressure for a reaction involving gases is given by the expression, `DeltaH = DeltaU + Deltan_(g) .RT`.

Define enthalpy and enthalpy change. Show that DeltaH = q_p .

What do you understand by enthalpy and change in enthalpy? Why does a chemical reaction involve a change in enthalpy?

If DeltaH is the enthalpy change and DeltaU the change in internal energy accompanying a gaseous reaction, then

If DeltaH is the enthalpy change and DeltaU the change in internal energy accompanying a gaseous reaction, then

If DeltaH is the enthalpy change and DeltaU the change in internal energy accompanying a gaseous reaction, then

Chemical reactions are invariably associated with the transfter of energy either in the form of heat or light. In the laboratory, heat changes in physical and chemical processes are measured with an instrument called calorimeter. Heat change in the process is calculated as {:(q = ms DeltaT,,s ="Specific heat"),(=cDeltaT,,c ="Heat capacity"):} Heat of reaction at constant volume is measured using bomb calorimeter. q_(V) = DeltaU = Internal energy change Heat of reaction at constant pressure is measured using simple or water calorimeter. q_(p) = DeltaH q_(p) = q_(V) +P DeltaV DeltaH = DeltaU +DeltanRT The enthalpy of fusion of ice is 6.02 kJ mol^(-1) . The heat capacity of water is 4.18 J g^(-1)C^(-1) . What is the smallest number of ice cubes at 0^(@)C , each containing one molw of water, the are needed to cool 500g of liquid water from 20^(@)C to 0^(@)C ?

In the relation DeltaH = DeltaU + (Deltan_(g))RT the units of Deltan_(g) is mol. (T/F)

Gibbs Helmholtz equation relates the enthalpy, entropy and free energy change of the process at constant pressure and temperature as DeltaG=DeltaH-TDeltaS " (at constant P, T)" In General the magnitude of DeltaH does not change much with the change in temperature but the terms TDeltaS changes appreciably. Hence in some process spontaneity is very much dependent on temperature and such processes are generally known as entropy driven process. Fro the reaction at 298 K, A_(2)B_(4)rarr2AB_(2) DeltaH=2" kJ" and DeltaS = 20 J/K at constant P and T, the reaction will be

Gibbs Helmholtz equation relates the enthalpy, entropy and free energy change of the process at constant pressure and temperature as DeltaG=DeltaH-TDeltaS " (at constant P, T)" In General the magnitude of DeltaH does not change much with the change in temperature but the terms TDeltaS changes appreciably. Hence in some process spontaneity is very much dependent on temperature and such processes are generally known as entropy driven process. When CaCO_(3) is heated to a high temperature it decomposes into CaO and CO_(2) , however it is quite stable at room temperature. It can be explained by the fact that

Chemical reactions are invariably assocated with the transfer of energy either in the form of heat or light. In the laboratory, heat changes in physical and chemical processes are measured with an instrument called calorimeter. Heat change in the process is calculated as: q= ms DeltaT , s= specific heat = c Delta T , c= heat capacity Heat of reaction at constant volume is measured using bomb calorimeter. qv= Delta U= internal energy change. Heat of reaction at constant pressure is measured using simple or water calorimeter. q_(p) = Delta H, q_(p) = q_(v) + P Delta V, DeltaH = DeltaU + Delta nRT The amount of energy released during a chemical change depnds on the physical state of reactants and products, the condition of pressure, temperature and volume at which the reaction is carried out. The variation of heat of reaction with temperature and pressure is given by Kirchhoff's equation: (DeltaH_(2)- DeltaH_(1))/(TT_(2)-T_(1)) = DeltaC_(P) (At constant pressure), (DeltaU_(2)- DeltaU_(1))/(TT_(2)-T_(1)) = DeltaC_(V) (At constant volume) The heat capacity of bomb calorimeter (with its contents) is 500J/K. When 0.1g of CH_(4) was burnt in this calorimeter the temperature rose by 2^(@)C . The value of DeltaU per mole will be