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      2. 
		
		
      
			
			
      
				
			
      
			
			
		
      
    
      
        
      
            
      
                
                    
      
	
      hydrogen
      
	
      英 ['ha?dr?d?(?)n]
美['ha?dr?d??n]

      


	    
      
	
        
    
      • n. [化學(xué)] 氫
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      考試真題
      
	
      
	
      Most hydrogen and oxygen atoms in water are stable, but traces of both elements are also present as heavier isotopes.
      2015年12月六級(jí)真題（第二套）聽(tīng)力 Section C