Research

DIFFERENCE BETWEEN EVAPORATION AND BOILING


Boiling only take place at 100 degree celcius
Evaporation takes place all the time

Normally evaporation occurs at a much slower rate than boiling because most evaporation occurs with room temperature water.

WHY EVAPORATION CAN CHANGE LIQUID STATE TO GASEOUS STATE BELOW BOILING POINT

As what i have mention earlier evaporation takes place all the time means that once the liquid gain heat it will evaporate hence evaporation can take place below 100 degree celcius.
WHY EVAPORATION OCCURS ONLY ON THE SURFACE WHILE BOILING OCCURS THROUGHOUT THE LIQUID



When we boiling water the heat source is below and heat travel upwards hence heat will be spread across the water. However in evaporation it takes place when ever there is heat and water that is in the cup only have a surface area for heat to contact which is the top hence evaporation does not take place with heat throughout the water.

IN NORMAL CIRCUMSTANCES, WHEN AN OBJECT COOLS, IT CONTRACTS, WHY LIQUIDS EXPAND WHEN IT COOLS?WHAT IS THE CRICTICAL TEMPERATURE FOR IT TO OCCUR?



Water's out-of-the-norm behavior is caused by the shape of its molecule and by how its molecules bond to one another.



Each water molecule is two hydrogen atoms bonded to one oxygen atom (H2O).



In liquid water, as molecules slip-slide past each other, bonds form, break, and re-form. But by the time water has cooled to 4 C., the molecules' energy has dropped enough that they are very near one another. So each H2O molecule forms more stable hydrogen bonds, with up to four fellow molecules. The crictical temperature for it to happen is 4 dgrees celcius.