The rate at which a solute dissolves in a solvent depends on the kinetic energy of the solution, the time of contact, and the surface area of contact between the solute and the solvent particles. both endothermic and exothermic dissolution processes will respond similarly to each factor, however the change may be more pronounced depending on the thermodynamic parameters of the reaction. as the kinetic energy, time of contact, and surface area of contact between the solute and the solvent particles increase, the rate at which the solute undergoes dissolution in a solvent increases. similarly, as the kinetic energy, time of contact, and surface area of contact between the solute and the solvent particles decrease, the rate at which the solute undergoes dissolution in a solvent decreases. the dissolution process can be altered by varying these parameters, such as by increasing or decreasing the temperature or by reducing the particle size of the solute. consider the preparation of a nacl salt solution using coarse crystals of nacl in an unstirred container at room temperature. classify the following conditions based on the change in the rate of dissolution of nacl in water compared to the initial preparation if the dissolution process is endothermic.

answer: c. the experiment shows that the red substance experienced a chemical change.

explanation: chemical change is the change in which chemical composition of the substance changes. physical change is the change in which there is no change in chemical composition.

chemical changes are accompanied by following changes:

a) precipitate formation

b) energy is released or absorbed

c) formation of bubbles

d) change in color

as it is given that the red color has disappeared and there is production of gas, it means the red substance has undergone a chemical change.

e

c. because step up transformer steps up the input voltage i.e increases the input voltage  

the number of turns are greater on the secondary side of step up transformer  

transformer does not handle dc current

plants need sunlight, water, and carbon dioxide to make food. plants use the raw materials of water, nutrients they absorb from soil, and carbon dioxide to make sugars the plant can use. energy from the sun and chlorophyll are also needed.

hurricanes form when warm, moist air from the ocean surface quickly rises into the atmosphere and forms storm clouds and rain. when the clouds are formed, heat is released which warms the cool air in the upper regions of the atmosphere so that the cycle can continue. which two phases of the water cycle are repeated in this process?