it is not a prescription drug
 
        
             
        
        
        
Compound.
Because compound is a substance formed by a chemical reaction of two or more separate elements. If a compound is separated, it would become two or more different substances instead of similar ones.
Wish this helps.
Bella from BOC Sciences
 
        
             
        
        
        
Properties and electron arrangement. Going down each column elements have similar properties and as they move left to right have the same number of electrons in their outer shell
        
             
        
        
        
(2) U-238 is the radioisotope used in dating geological formations. Uranium-238 has a half-life of 4.46 billion years, which makes it suitable to date such old formations.
The other options do not have such long durabilities and half-lives.
        
                    
             
        
        
        
Answer:
HF - hydrogen bonding
CBr4 - Dispersion
NF3 - Dipole-dipole
Explanation:
Hydrogen bonding occurs when hydrogen is covalently bonded to a highly electronegative atom such as fluorine, chlorine nitrogen, oxygen etc. Hence the dominant intermolecular force in HF is hydrogen bonding.
CBr4 is nonpolar because the molecule is tetrahedral and the individual C-Br dipole moments cancel out leaving the molecule with a zero dipole moment hence the dominant intermolecular force are the dispersion forces.
NF3 has a resultant dipole moment hence the molecules are held together by dipole-dipole interaction.