Answer:
A
Explanation:
always more reactants than products
 
        
             
        
        
        
Answer: False
Explanation:
Molecular formula is the chemical formula which depicts the actual number of atoms of each element present in the compound.  
Empirical formula is the simplest chemical formula which depicts the whole number of atoms of each element present in the compound.
Example:  has similar molecular formula and empirical formula as the elements are already present in simplest of the ratios.
 has similar molecular formula and empirical formula as the elements are already present in simplest of the ratios.
 has molecular formula of
 has molecular formula of  but
 but  as the empirical formula.
 as the empirical formula.
 
        
             
        
        
        
Answer: Think and you will get it right!
Explanation:
To find the mass percent composition of an element, divide the mass contribution of the element by the total molecular mass. This number must then be multiplied by 100% to be expressed as a percent.