Explanation:
In first one it should be 2Mg
and in second = 2Mgo
hope it helps....
 
        
             
        
        
        
Answer:
Water acts as a base in the presence of a strong acid
Explanation:
Water,being an amphoteric compound, can act both as an acid and as a base. 
In the presence of an acid , water acts as a base but in the presence of a base, water acts as an acid.
 
        
             
        
        
        
Answer and Explanation:
The balanced chemical equations are as follows:
The chemical formula of oxalic is  
In the case when oxalic acts reacted with the water so here the oxalic acid eliminates one proton that leads to the development of mono acids
After that, the second step derives that when oxalic acid is in aqueous solution eliminates other proton so it represent the polyprotic acid
Now the chemical equations are as follows:
Elimination of one proton 

Now the elimination of other proton

 
        
             
        
        
        
D. All of the above are indicators of chemical change
        
             
        
        
        
Answer:
It is an exothermic reaction. Heat must be added to light the fuses of the fireworks
Explanation:
I learned this in high school chemistry.