Sakshi Roll No. 12 MATTER IN OUR SURROUNDING

         Chapter :1 Matter in our surrounding 

 Date 4/4/16

 Question- why do we observe that the level of water is not change en after dissolving the salt?

 Answer- As we all know that water is made up of matter which is made up f particles, these particles have various gaps ,which are filled with salt when we dissolve the salt, Thus, the level of water does not change even after dissolving the salt. 

 DATE-5/4/16

 PROPERTIES OF PARTICLES There are three properties of matter these are:

 i. The particles of the matter are very small.
 ii. The particles of matter are continuously moving .
 iii. Means they have KINETIC ENERGY. 
iv. The particles of mater have space between them. 

DATE :6/4/16

QUESTION: WHY SOLID HAVE FIXED SHAPE?

 ANSWER: Solids have fixed shapes because they are very tightly packed,which do no allow to molecules to move from one place to another place so they have fixed shapes 

Date: 7/4/16

Question: give reasons the:

                    Table is hard

                     Diver Is able to cut the water

                     The smell of hot sizzling food reach to our

                       nose.

Answer;  

table is hard because the molecules are tightly packed, they cannot move, there force of attarcton is very high, these are the reasons that why table is hard.

The diver is able to cut the water easily because the   matter of liquid are not tightly packed, they can also move from one position to another position, and the force of attraction of liquid is less,

Thus, the diver is able to cut the water.

The smell of hot sizzling food can reach to our nose because the air coming out from food is get easily

Intermix with air particle ,and the hot air coming out from food posses the kinetic energy thus the particles  can move easily move so they reaches to our nose

date:12/04/16

 DEFINE:

   Latent heat of vaporisation:  Latent heat of  vaporisation is heat  energy required to change 1 kg of liquid to gas at atmospheric pressure at its boiling point.

 Latent heat of fusion: Latent heat of fusion is the amount of heat energy required to change 1 kg of solids into at its melting  point.

 

DATE: 13/04/16

FACTORS AFFECTING TO EVAPORATION

1    An increase of surface area:

 If the surface area is increased, the rate of evaporation increased.

 2 An increased of temperature:

The increase of temperature, more number of particle get enough kinetic enrgy to go into the vapour state.

  3 A  decrease in humidity:

Humidity is the amount of water vapour present in air.the air around us

Cannot hold more then a definite amount of water vapour at a given temperature.if the amount of water in air is already high,the rate of evaporation decrease.

  4 An increased in wind speed:

The increased in wind speed ,the particle of water vapour move away with the wind decreasing the water vapour in the surrounding.



  THE FUNDAMENTAL UNIT OF LIFE -

 CELL

Date: 21/04/16

why does water come out from cucumber when we add salt to it ?

water come out from cucumber when we add salt to it because the content of salt that cucumber is less where as the salt in its  surrounding has high salt content , so to  get balance salt drawn from the  cucumber .