Hey there!:
density  = 3.51 g/cm³
Volume = 0.0270 cm³
Therefore:
D = m / V
3.51 = m / 0.0270
m = 3.51 * 0.0270
m = 0.09477 g 
        
                    
             
        
        
        
Answer: On heating, Magnesium forms its oxide; while potassium manganate(VII) decomposes
Explanation:
Magnesium Mg, on heating forms Magnesium oxide 
 2Mg(s) + O2(g) --> 2MgO
Potassium permanganate KMnO4, on heating decomposes to potassium manganate K2MnO4, manganese dioxide MnO2, and Oxygen gas O2.
2KMnO4 --> K2MnO4 + MnO2 + O2
The difference in observation is that, on heating, Magnesium forms its OXIDE as product; while potassium manganate(VII) decomposes, giving OFF most of its constituents and reducing its weight.
 
        
             
        
        
        
Answer:
The gain in mass by the negative electrode is the same as the loss in mass by the positive electrode. So the copper deposited on the negative electrode must be the same copper ions that are lost from the positive electrode.
 
        
             
        
        
        
BE CAREFUL! If it is a controlled lab wear saftey equiptment. But it can blow up. So careful...
        
             
        
        
        
Answer:
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