Answer: Option (C) is the correct answer.
Explanation:
Movement of particles in a substance is responsible for change in state of the substance or matter.
This means that more is the motion of particles more will be their kinetic energy.
Also, kinetic energy is directly proportional to temperature.
K.E = 
So, less is the temperature of an object or substance less will be be the motion of its particles. Therefore, molecules will come closer to each other and state of substance will change from liquid to solid.
Thus, we can conclude that the motion of the molecules would decrease at a molecular level if a liquid is placed in cool conditions.
Answer:
The activation energy
Explanation:
The activation energy is the energy hump that lies between reactants and products. It is the energy barrier that reactants must cross before they are converted into products.
Based on the collision theory, only particles that possess the activation energy are able to collide in such a way that leads to reaction.
Collision of particles having an energy content less than the activation energy of the reaction merely leads to elastic collision between such particles.
Answer:
Milk is essentially a colloidal dispersion of fat in water. ... However, the fact remains that the fat and water components cannot be mixed together from a solution. There are therefore, two distinct immiscible liquid phase's present, which is why it is a heterogeneous mixture.
Answer: A chemical process must occur and then changes between the state of the reactants and the state of the products can be determined
Explanation: Enthalpy represents the sum of the energy of the system with the product of the pressure and volume of that system. As a thermodynamic property, it expresses the ability to release heat from the system. In fact, enthalpy tells us how much heat and work has changed during the chemical reaction under constant pressure. When measuring, measurements of the difference in enthalpy between the two states of the system is performed, before and after the chemical reaction, since total enthalpy can not be measured. This measurement of the enthalpy change can tell us, for example, whether the heat was released from the system during the reaction, or the system absorbed the heat.
