Chemical weathering is caused by rain water reacting with the mineral grains in rocks to form new minerals (clays) and soluble salts. These reactions occur particularly when the water is slightly acidic.
        
             
        
        
        
Answer:
Acid-base  
Explanation:
KOH is a strong base, and NH₄Cl is an acid. They react to form a salt and water.
KOH + NH₄Cl ⟶ NH₃ + KCl + H₂O
base     acid                    salt   water
 
        
             
        
        
        
Answer: 19
Explanation:
In order to write the Potassium electron configuration we first need to know the number of electrons for the K atom (there are 19 electrons). When we write the configuration we'll put all 19 electrons in orbitals around the nucleus of the Potassium atom.