Question

Which changes of state are characterized by having atoms that gain energy?

Answer 1

Hey there!

When atoms gain energy, they change to different states of matter. Two changes of state are defined by this concept. They are: boiling, and evaporating.

During boiling, water exceeds or reaches it's boiling point of 212 degrees Fahrenheit and becomes hot. When the atoms reach this point of heat, they gain energy and start to move so fast they become steam, or water in its gaseous form.

Next, we have evaporation. Evaporation is commonly known as a part of the water cycle. When water becomes too hot, atoms gain energy and start becoming gas - eventually to become clouds if we're talking about the cycle.

Hope this helps!

Answer 2

Answer:

When we heat a solid substance and if it changes into liquid state then this process is known as melting.

Since, heat is provided to melt the substance therefore, there will be high kinetic energy of molecules. Hence, energy is gained by molecules.

When a solid changes directly into gaseous state without undergoing liquid state then this process is known as sublimation.

For example, naphthalene ball reduces in size when left for long period of time shows sublimation.

Since solid changes into gas therefore, energy is gained in sublimation.

In freezing, molecules come close to each other as molecules come to rest. Thus, there is no gain of energy in freezing.

In vaporization, liquid changes into vapour or gaseous state. Therefore, energy is also gained in vapourization.

In condensation, vapour or gases change into liquid state. This means there will be decrease in kinetic energy of molecules. Hence, there will be no gain of energy in condensation.

In deposition, molecules come to rest at one place. Therefore, there will be no gain of energy in deposition.

Thus, we can conclude that following changes of state are characterized by having atoms that gain energy:

Melting.

Sublimation.

Vapourization.