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[Chem] 求答案解釋

求答案解釋

Please help for below 3 MC below (need explanation)
1. When a piece of potassium is put into 1 M sodium hydroxide solution
A. hydrogen gas and potassium hydroxide will be formed
B. hydrogen gas and potassium oxide will be formed
C. oxygen gas will be formed
D. sodium and potassium hydroxide will be formed
Ans is A.

2. 1st statement - When zinc and lead are exposed to air, zinc corrodes faster than lead
2nd statement - Zinc loses electrons more readily than lead
Ans: Both statement are true but 2nd statement is NOT a correct explanation of the 1st statement.

3. 1st statement - Ammonium chloride is not an electrolyte
2nd statement - Ammonium chloride is made up of non-metals only.
Ans: Both statement are true but 2nd statement is NOT a correct explanation of the 1st statement.

Thank you very much !!!
   

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[隱藏]

why is there no response ?

   pls help

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My explaination

1. Potassium reacts with water preferentially to produce hydrogen in this reaction as it is very reactive, then replacement reaction would occur between sodium ion and potassium, hence
2K + 2H2O = 2K+ + 2OH- + H2
K + Na+ = K+ + Na
Summing up the above equations would form hydrogen gas and KOH

2. Zinc corrodes in air easily but lead only corrodes in air in heat. Zinc doesn't sacrifice its electrons to prevent lead from corrosion in this case.

3. Ammonium chloride is covalent compound with a dative bond, so it doesn't ionise and it's not an electrolyte.



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