Chemical bonds in chemisorption are much stronger.
Physisorption is weaker than chemisorption and is typically dependent on van der Waals forces. As temperature increases, the thermal energy disrupts these weak interactions between the adsorbate and the surface, leading to a decrease in physisorption.
The ionisation enthalpy of potassium is lower than that of sodium.
If you plot the reaction coordinate (what I think you mean by "enthalpy change diagram"), the reaction will be exothermic if the products are lower on the graph than the reactants. If they are higher than it is endothermic. For instance, if you go to the linked Wikipedia page (link to the left of this answer), the graph shown is of an exothermic reaction.
Negative enthalpy refers to a situation in which a process or reaction releases energy, typically in the form of heat, to its surroundings. This indicates that the enthalpy change (ΔH) for the reaction is less than zero, signifying an exothermic process. In practical terms, reactions with negative enthalpy contribute to an increase in the temperature of their environment, often making them spontaneous under certain conditions.
The ethanol enthalpy of vaporization is lower compared to water.
Physisorption is weaker than chemisorption and is typically dependent on van der Waals forces. As temperature increases, the thermal energy disrupts these weak interactions between the adsorbate and the surface, leading to a decrease in physisorption.
The ionisation enthalpy of potassium is lower than that of sodium.
If you plot the reaction coordinate (what I think you mean by "enthalpy change diagram"), the reaction will be exothermic if the products are lower on the graph than the reactants. If they are higher than it is endothermic. For instance, if you go to the linked Wikipedia page (link to the left of this answer), the graph shown is of an exothermic reaction.
The difference between the bond enthalpy of the reactants and the bond enthalpy of the products in a chemical reaction represents the energy change that occurs during the reaction. If the bond enthalpy of the products is lower than that of the reactants, it indicates that energy is released during the reaction, making it exothermic. Conversely, if the bond enthalpy of the products is higher than that of the reactants, it indicates that energy is absorbed during the reaction, making it endothermic.
The enthalpy change of atomization of bromine is higher than its bond enthalpy because it accounts for breaking the diatomic molecule into individual bromine atoms in the gas phase, which requires overcoming intermolecular forces. Bond enthalpy, on the other hand, only considers the energy needed to break the specific bond in a molecule, not breaking the entire molecule into individual atoms.
Physisorption is the reversible adsorption of molecules onto a surface due to weak van der Waals forces. It involves physical interactions rather than chemical bonds, and can occur in processes such as gas adsorption on solid surfaces.
In an exothermic reaction the energy of the products is less than that of the reactants.
The molar enthalpy of fusion of ice is relatively high compared to the molar enthalpy of fusion of many other solids. This is because ice requires a significant amount of energy to change from a solid to a liquid state due to its strong hydrogen bonds. However, there are some solids, such as metals, that have higher molar enthalpies of fusion than ice.
If the ∆H is positive and the ∆S is positive, then the reaction is entropy driven. If the ∆H is negative and the ∆S is negative, then the reaction is enthalpy driven. If ∆H is positive and ∆S is negative, then the reaction is driven by neither of these. If ∆H is negative and ∆S is positive, then the reaction is driven by both of these.
Endothermic reaction: In an endothermic reaction, the products are higher in energy than the reactants. Therefore, the change in enthalpy is positive, and heat is absorbed from the surroundings by the reaction therefore enthalpy change show positive sign in a endothermic reaction..
The enthalpy of Cl2 (chlorine gas) is higher than 2 Cl (two atoms of chlorine). This is because forming Cl2 from two Cl atoms involves the breaking of an existing bond between the atoms, which requires energy input, whereas 2 Cl atoms do not require this bond formation energy.
Sodium has only one valence electron, and when that is donated to some other atom, the remaining ion has a noble gas configuration that is highly stable. Disrupting that by another ionization requires much energy. Magnesium has two valence electrons; therefore the second is almost as easy to donate as the first. The third ionization enthalpy of magnesium would be very high.