Food. Temperature holds great importance for both food manufacturers and those simply looking to cook at home. Whether barbecuing or waiting for the water to boil, temperature is important in preparing a meal; it can affect the quality, flavor, and freshness of food.

Temperature is among the most pervasive and important physical factors in the environment of an organism. Properties such as viscosity or fluidity, and changes in state from solid to liquid to gas, depend upon temperature. Diffusion rates increase as temperature increases, because the particles are moving faster.

There are three temperature scales in use today, Fahrenheit, Celsius and Kelvin. Fahrenheit temperature scale is a scale based on 32 for the freezing point of water and 212 for the boiling point of water, the interval between the two being divided into 180 parts.

Warmer temperatures can also lead to a chain reaction of other changes around the world. That’s because increasing air temperature also affects the oceans, weather patterns, snow and ice, and plants and animals. The warmer it gets, the more severe the impacts on people and the environment will be.

The heart rate increases to pump more blood through outer body parts and skin so that excess heat is lost to the environment, and sweating occurs. These changes place additional demands on the body. Changes in blood flow and excessive sweating reduce a person’s ability to do physical and mental work.

Temperature extremes can also worsen chronic conditions such as cardiovascular disease, respiratory disease, cerebrovascular disease, and diabetes -related conditions. Prolonged exposure to high temperatures is associated with increased hospital admissions for cardiovascular, kidney, and respiratory disorders.

Chemisorption initially increases then decreases with rise in temperature. The initial increase is due to the fact that heat supplied acts as activation energy. The decrease afterward is due to the exothermic nature of adsorption equilibrium.

The chemical bonds formed in chemisorption are of ionic or covalent in nature. They involve a high activation energy so known as activated adsorption. As the formation of chemical bonds occurs in chemical adsorption, high temperature is favorable.

The initial increase in chemisorption is due to the fact that the heat supplied acts as activation energy and more and more molecules of adsorbate gain energy and possess energy greater than activation energy. Therefore, adsorption increases with increase in temperature.

As the surface area of adsorbent increases, the rate of this process increases. Extent of physisorption is more in finely divided metal particles or in porous materials. This is an exothermic process that means heat is evolved in this process. So, the rate of physisorption decreases with increase in temperature.

Increasing the temperature decreases the value of the equilibrium constant. Where the forward reaction is endothermic, increasing the temperature increases the value of the equilibrium constant. The position of equilibrium also changes if you change the temperature.

Temperature has different effect in physisorption and chemisorption. (i) In Physisorption. An increase in temperature will favourthe desorption process because molecules of the adsorbate get energy and leave the surface so rate of adsorption decreases with increase in temperature.

Why do physisorption and chermisorption behave differently with rise in temperature ? Physisorption involves weak van der Waals’ forces which weakens with increase in temperature. Chemisorption involves formation of chemical bond which requires activation energy hence, it is favoured by rise in temperature.

It occurs slowly at low temperature and occurs at a higher rate with increase in pressure. Just as in case of physisorption, chemisorption is directly proportional to surface area and thus increases with increase in surface area. Since the process involves chemical bond formation, the enthalpy in high.

Answer: Chemical adsorption of a gas on solid first increases and then decreases with increase in temperature. The forces of attraction between adsorbent and adsorbate are of Van der Waals type (weak forces).

Physisorption involves weak van der Walls’ forces. The magnitude of these forces decreases with rice in temperature. The chemisorption involves formation of chemicl bonds between the molecules of adsprbae and adsorbent. Therefore, chemisorption increases as the temperature increases.

Difference Between Physisorption And Chemisorption

It is an exothermic process which means that energy is liberated during this process. The reason behind this is that when adsorbate molecules are adsorbed on the surface, freedom of movement of molecules become restricted and this results in a decrease in entropy. …

Answer : In Physisorption the adsorbate molecules are held by weak van der Waal’s forces, so on decreasing the pressure it is reversible. Chemisorption involves strong chemical bonding between adsorbate and adsorbent molecules which is difficult to reverse and hence it is irreversible.

Physisorption takes place with the help of non-covalent bonding between an adsorbate and an adsorbent; it makes the process reversible. Chemisorption, on the other hand, takes place with the help of covalent bonding; it makes the process irreversible.