Answer:
the specific heat of the unknown compound is 
Explanation:
Generally the change in temperature of water is evaluated as 
                 
Substituting 16.1°C for  and 27.4°C for
 and 27.4°C for 
                 
                        
Generally the change in temperature of  unknown compound is evaluated as
                   
Substituting 27.4°C for  and 94.3°C for
 and 94.3°C for 
                                     
                                            
Since there is an increase in temperature then heat is gained by water and this can be evaluated as
                
Substituting 179.1 g  for m , 4.18 J/g.C for  (specific heat of water)
(specific heat of water)
              
                    
Since there is a decrease in temperature then heat is lost by unknown compound and this can be evaluated as
                     
By conservation of energy law 
        Heat lost  = Heat gained  
Substituting 306.9 g  for  , 8459.6J for
 , 8459.6J for  
 
            
   Therefore     
                            
                    
 
        
             
        
        
        
Answer:
Density independent factor
Explanation:
in dense areas where people livein  very close and tight spaces
 
        
             
        
        
        
The reason that some of the elements of period three and beyond are steady in spite of not sticking to the octet rule is due to the fact of possessing the tendency of forming large size, and a tendency of making more than four bonds. For example, sulfur, it belongs to period 3 and is big enough to hold six fluorine atoms as can be seen in the molecule SF₆, while the second period of an element like nitrogen may not be big to comprise 6 fluorine atoms.  
The existence of unoccupied d orbitals are accessible for bonding for period 3 elements and beyond, the size plays a prime function than the tendency to produce more bonds. Hence, the suggestion of the second friend is correct.  
 
        
             
        
        
        
Answer: (3) The difference in electronegativity between  carbon and oxygen is greater than that  between fluorine and oxygen.
Explanation: Polarity of a molecule is due to the difference in electronegativity of the atoms. More is the electronegativity difference, more is the polarity.
Electronegativity of carbon = 2.5
Electronegativity of oxygen = 3.5
Electronegativity of fluorine = 4.0
Thus the difference in electronegativity of carbon and oxygen is=(3.5-2.5)= 1.0
Thus the difference in electronegativity of fluorine and oxygen is=(4.0-3.5)= 0.5.
Thus C-O bond is more polar than F-O bond.