The answer is A because it’s how you calculate the mass
        
             
        
        
        
The mass would be same because of the law of conservation which states that the mass of the reactants must equal to the mass of products
        
             
        
        
        
Answer:
Temperature decreases and density increases
Explanation:
Let us remember that density of a material increases as the temperature of the material decreases. So the cooler a material becomes, the denser it becomes also.
Between points B and C, the material rapidly cools down and the temperature decreases accordingly. This ultimately results in an increase in density since cooler materials are denser than hot materials.
 
        
             
        
        
        
Answer:
-1160kj/mol
Explanation:
the reaction is exothermic because heat is released to the environment
 
        
             
        
        
        
D. The particles are tightly packed together