Answer:
(NH₄)₂CO₃ (aq) + MgSO₄(aq)  →  (NH₄)₂SO₄(aq) + MgCO₃ (s) ↓  
Explanation:
We determine the reactants:
(NH₄)₂CO₃ → Ammonium carbonate
MgSO₄ → Magnesium sulfate
We determine the products:
(NH₄)₂SO₄ ; MgCO₃
All the salts from carbonates are precipitates:
(NH₄)₂CO₃ (aq) + MgSO₄(aq)  →  (NH₄)₂SO₄(aq) + MgCO₃ (s) ↓  
Ratio is all 1:1. 1 mol of ammonium carbonate reacts to 1 mol of magnessium sulfate in order to produce 1 mol of ammonium sulfate and 1 mol of magnessium carbonate.
 
        
             
        
        
        
It may have less attractive forces between their atoms
        
             
        
        
        
First convert 12.0g of Na to moles using the grams to moles conversation and you get about .5219 moles (I didn't use significant figures). Divide that number by 3 because that is the coefficient of Na and you will get about .17398 moles, which is how many moles are in 1. Since Al has a coefficient of 1, .17398 woild be your final answer
        
             
        
        
        
Answer:
4.35 * 10^-8 M
Explanation:
Since the concentration of the hydronium ion= 2.3 X 10^-7 M
And we know that;
[H3O^+] [OH^-] = 1 * 10^-14
[H3O^+]  = concentration of the hydronium ion
[OH^-] = concentration of the hydroxide ion
So;
[OH^-] =1 * 10^-14/[ H3O^+]
But [H3O^+] = 2.3 X 10^-7 M
[OH^-] = 1 * 10^-14/2.3 X 10^-7
[OH^-] = 4.35 * 10^-8 M
 
        
             
        
        
        
Answer:4)Wind energy can harm migrating birds.
Explanation: