Shielding electrons are the electrons in the energy levels between the nucleus and the valence electrons. They are called "shielding" electrons because they "shield" the valence electrons from the force of attraction exerted by the positive charge in the nucleus. Hope this helps!!
 
        
                    
             
        
        
        
Explanation:
Upon dissolution of KCl heat is generated and temperature of the solution raises.
Therefore, heat generated by dissolving 0.25 moles of KCl will be as follows.
              
                 = 4.31 kJ
or,             = 4310 J      (as 1 kJ = 1000 J)
Mass of solution will be the sum of mass of water and mass of KCl.
        Mass of Solution = mass of water + (no. of moles of KCl × molar mass)
                                     = 200 g + 
                                     = 200 g + 13.625 g
                                     = 213.625 g
Relation between heat, mass and change in temperature is as follows.
                              Q = 
where,    C = specific heat of water = 
Therefore, putting the given values into the above formula as follows.
                      Q = 
             4310 J =  
      
                
 
Thus, we can conclude that rise in temperature will be  .
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 I think only solids arrange in a regular geometric pattern, so i2
        
             
        
        
        
Answer: Gas
Explanation:
since the gas molecules arent being forcefully bonded together like a solid would be, and liquids tend to have lower kinetic energy than solids
 
        
             
        
        
        
Answer: ^_^
Explanation: 
its because during day time the ball becomes heated up and the air inside it try to come out as the heat air always try to go up swelling up the ball,
so in the evening when the air cools down the ball too cools down and air inside it also cools down making the ball feel soft,
Therefore, a football feels hard on a hot day but feels softer in the evening
Hope it helped u,
pls mark as the brainliest
^_^