potassium reacts the most vigorously.
 
        
             
        
        
        
In the modern periodic table when elements are arranged according to their atomic number.
        
             
        
        
        
Answer:
 they need to do their research 
 
        
                    
             
        
        
        
Answer: A index fossil is any animal or plant preserved in the rock record of the earth that is characteristic of a particular span of geologic time or environment. A useful index fossil must be distinctive or easily recognizable, abundant, and have a wide geographic distribution and a short range through time.
Explanation:
 
        
             
        
        
        
We can express the rate equation in this form:
-r = k A^n B^m
where -r is the rate
k is the rate constant,
A is the concentration of CH3Cl
n is the order with respect to CH3Cl
B is the concentration of H2O
m is the order with respect to H2O
We can solve this by trial and error or by calculus. The first method is easier. The rate constant does not depend on the concentration of the reactant. Assume values of n and m and solve for k in each experiment. The only option that gives really close values of k in each experiment is:
<span>C. CH3Cl: firstorder H2O: second order
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