1s^2 = filled
2s^2 = filled
2p^6 = filled
3s^1 = partially filled (need 2) 
3 orbitals are completely filled.
        
             
        
        
        
Answer:
Polythene has the lowest melting/boiling point from all the other covalent structures mentioned in this question.
 
        
                    
             
        
        
        
Answer:
D. has different properties when sampled in different areas.
Explanation:
The general property of a mixture says that each substance or component in a mixture has its individual or different property which can be separated on the basis of different methods.
Such as a mixture of oil and water is a heterogeneous mixture and have different properties or different densities, which helps them to be sampled in different areas.
Hence, the correct answer is "D".
 
        
             
        
        
        
<h2><em>Solid. Because molecules densely packed it has a high resistance to flow thereby lower kinetic energy.
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