3.
1. 2Fe + 3Cu(NO₃)₂⇒ 2Fe(NO₃)₃ + 3Cu
2. Zn + Cu(NO₃)₂⇒ Zn(NO₃)₂ + Cu
3. 3Zn + 2Fe(NO₃)₃⇒ 3Zn(NO₃)₂ + 2Fe
4. Fe³⁺ reduced to Fe (oxidation number from +3 to 0)
Metal(s) acted as reducing agents : Zn
Further explanation
There are two types of chemical reactions that may occur,
single-replacement reactions and double-replacement reactions.
A single replacement reaction is a chemical reaction in which one element replaces the other elements of a compound to produce new elements and compounds
Not all of these reactions can occur. We can use the activity series, which is a list of elements that can replace other elements below / to the right of them in a single replacement reaction.
This series is better known as the Volta series, where the metal element with a more negative electrode potential is on the left, while the element with a more positive electrode potential on the right.
The more left the position of a metal in the series, the more reactive metal (easy to release electrons, the stronger the reduction)
Generally, the Volta series used is
Li K Ba Sr Ca Na Mg Al Mn Zn Cr Fe Cd Co Ni Sn Pb H Sb Bi Cu Hg Ag Pt Au
3.
Fe and Zn element can replace the Cu element, which is on the right side so the reaction will occur
Zn also can replace Fe which is on the right side
1. 2Fe + 3Cu(NO₃)₂⇒ 2Fe(NO₃)₃ + 3Cu
2. Zn + Cu(NO₃)₂⇒ Zn(NO₃)₂ + Cu
3. 3Zn + 2Fe(NO₃)₃⇒ 3Zn(NO₃)₂ + 2Fe
4. Yes, Fe³⁺ reduced to Fe (oxidation number from +3 to 0)
Metal(s) acted as reducing agents : Zn
