Considering that scientific notation has to move the decimal over so there is only one digit in the Tens place, that is the scientific notation.
        
                    
             
        
        
        
Answer: m = 11.2 g C7H16
Explanation: First convert the mass of CO2 to moles. Then do the mole ratio between CO2 and C7H16 which is 7:1. Finally convert the moles of C7H16 to the mass of C7H16.
Solution attached.
 
        
                    
             
        
        
        
A molecular formula represents the exact number of atoms present for each element in the compound.  
For carbon atom:  =
 =  ( as molar mass of carbon is 12 g/mol)
 ( as molar mass of carbon is 12 g/mol)
Now, 6 carbon atoms are present and rest are hydrogen atoms i.e. 6
Thus, formula becomes  (
 (  
 
Now, check for unsaturation:
Degree of unsaturation  = 
Substitute the value of x and y,
Degree of unsaturation  = 
= 
=  implies one ring and three double bonds.
 implies one ring and three double bonds.
Thus, formula comes out to be  i.e. benzene ring.
 i.e. benzene ring.
 
        
             
        
        
        
B. False. An alpha particle is a Helium nucleus which has a mass of 4 as it is made from 2 neutrons and protons each with mass of +1.