Why do old people shiver more in winter when compared to youngsters? Is there any special arrangement to prevent the escape of heat energy during winter?

Is there any insulator like substance to prevent the escape of heat energy during winter?

During winter mornings why do people stand in the Sun? Explain.

During winter, body shivers. Why?

The bond dissociation energy depends upon the nature of the bond and nature of the molecule. If any molecule more than 1 bonds of similar nature are present then the bond energy reported is the average bond energy. Heat evolved when 0.75 mol of molten aluminium at its melting point of 658^(@)C is solidified and cooled to 25^(@)C . The enthalpy of fusion of aluminium is 76.8 "cal" g^(-1) and C_(P)= 5.8 "cal" mol^(-1) ""^(0)C

Why do we experienced cloud like smoke near our mouth while speak during the winter season?

For a spontaneous reaction, the free energy change must be negative. DeltaG=DeltaH-TDeltaS is the enthalpy change during the reaction. T is absolute temperature, and AS is the change in entropy during the reaction. Consider a reaction such as the formation ofan oxide . M+O_(2) MO Dloxygen is used wp in the course of this reaction. Gases have a more random structure (less ordered) than liquid or solids consequently gases have a higher entropy than liquids and solids, in this reaction (entropy or randomness) decreases, hence is negative. Thus, the temperature is raised the DeltaS becomes more negative. Since, TDeltaS is subtracted in the equation, then SG becomes less negative. Thus, the free energy changes increases with the increase in temperature. The free energy changes that occur when one mole of common reactant in this case dioxygen) is we may e plotted graphically against temperature for a number of reactions of metals to their oxides. The following plot is called an Ellingham diagram for metal oxide. Understanding of Ellingham diagram is extremely important for the efficient extraction of metals. Which of the following elements can be prepared by heating the oxide above 400^(@)C ?

Which type of blended fabric do you find more comfortable in winter? Why?

Explain why (a) Two bodies at different temperatures T_(1) and T_(2) if brought in thermal contact do not necessarily settle to the mean temperature (T_(1) + T_(2))//2 . (b) The coolant in a chemical or a nuclear plant (i.e., the liquid used to prevent the different parts of a plant from getting too hot) should have high specific heat. (c) Air pressure in a car tyre increases during driving. (d) The climate of a harbour town is more temperate than that of a town in a desert at the same latitude.