Answer:
the lowest point of energy the the graph reaches
 
        
             
        
        
        
Answer:
IV
Explanation:
The complete question is shown in the image attached.
Let us call to mind the fact  that the SN1 mechanism involves the formation of carbocation in the rate determining step. The order of stability of cabocations is; tertiary > secondary > primary > methyl.
Hence, a tertiary alkyl halide is more likely to undergo nucleophilic substitution reaction by SN1 mechanism since it forms a more stable cabocation in the rate determining step.
Structure IV is a tertiary alkyl halide, hence it is more likely to undergo nucleophilic  substitution reaction by SN1 mechanism.
 
        
             
        
        
        
For better representation, let me rewrite the electronic configuration:
<span>1s</span>²<span>2s</span>²<span>2p</span>⁶<span>3s</span>²<span>3p</span>⁶<span>4s</span>²<span>3d</span>⁴
The exponents represent the number of electrons in the designated subshell. Thus, the total number of electrons are:
# of electrons = 2+2+6+2+6+2+4 = 24
Assuming this is in neutral state, the element with an atomic number of 24 is Chromium. Thus, the answer is Cr.
        
             
        
        
        
Answer:
Classification will be Potassium, Bromine, and Argon
Explanation:
- Potassium is more likely to lose electrons and form positive ion
- Bromine actually gain electrons and forms negative ion
- Argon does not lose or gain electrons