1.7960L
 
Explanation:
the mass of the gas is constant in both instances
pv/T=constant(according to pv=nRT)
 745mmHg*2L/298K=760mmHg*v/273K
 v=1.7960L
 
        
             
        
        
        
Use the formula E=mc^2
energy given=<span>8.1 x 10^16 joules
</span>speed of <span>light = 3.00 × 10^8 m/s
</span>
plug in the values we'll get mass=<span>9.0 x 10-1 kg</span>
        
                    
             
        
        
        
The best substance to heat up the fastest would be blue fire
        
                    
             
        
        
        
A.)Neutral. Since amount of protons and electron are equal and amount of protons cannot be changed so it is stable or neutral.
 
        
                    
             
        
        
        
Answer:  obey the "law of conservation of mass".
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