Answer:
The number of moles of Sr in one mole of Sr(HCO₃)₂ = 1 mole
The number of moles of H in one mole of Sr(HCO₃)₂ = 2 moles
The number of moles of C in one mole of Sr(HCO₃)₂ = 2 moles 
The number of moles of O in one mole of Sr(HCO₃)₂ = 6 moles
Explanation:
The given chemical formula of the compound is Sr(HCO₃)₂
The number of atoms of Sr in the compound = 1
The number of atoms of H in the compound = 2
The number of atoms of C in the compound = 2
The number of atoms of O in the compound = 6
The number of atoms of each element present in each formula unit of Sr(HCO₃)₂ is proportional to the number of moles of each atom in one mole of Sr(HCO₃)₂ 
Therefore;
The number of moles of Sr in one mole of Sr(HCO₃)₂ = 1 mole
The number of moles of H in one mole of Sr(HCO₃)₂ = 2 moles
The number of moles of C in one mole of Sr(HCO₃)₂ = 2 moles 
The number of moles of O in one mole of Sr(HCO₃)₂ = 6 moles.
 
        
             
        
        
        
The answer is A. Ne. You can separate the elements in the other three choices through chemical changes (dissociation, ionization, electrolysis, etc.), but in order to separate the components of Ne, you would need a nuclear reaction (to decompose the nucleus) or a physical change (to strip the nucleus of its electron cloud).
        
                    
             
        
        
        
The molecules vibrate when the substance is heated, and the shape of the substance begins to form a different shape. For example: when you hear up metal it will melt becuase its molecules are changing and moving.
 
        
                    
             
        
        
        
Answer:    
As there must be twice as many lithium ions as sulphide ions, the 'numbers' 
must be different. 
 It's 4:8. i.e. 4 sulphides around each lithium; and 8 lithiums around each 
sulphur. 
 It's an antifluorite structure.