Step-by-step explanation:
1). 2Cs + F2 ---> 2CsF
assigning the oxidation number to reactants and products of the above reaction:
Reactant = Cs + F2 (oxidation number of Cs = +1, oxidation number of F2 = 0)
Product = CsF ( Oxidation number of Cs in CsF is +2 and F is -1)
oxidized element in the reaction is one with increase in oxidation number
Oxidation number of Cs increases from +1 to +2
F is reduced because oxidation number is decreased from 0 to -1.
F is the oxidizing agent because it got reduced in the reaction.
2). Balanced equation:
Sn + HNO3 ---> SnO2 + NO2 + H2O
oxidation numbers 0 +1+5 -2 ⇔ -2+4-2 +4-2 +1-2
oxidation reaction= Sn ⇒ SnO2 + 4 e-
0 +4 -2
reduction reaction = HNO3 + e- ⇒ NO2
+1+5-2 +-2
combining the oxidation and reduction reaction equation, we will balance them by balancing the charges on them.
Sn + 2H2O ⇒ SnO2 + 4 e- +4 H+
HNO3 + e-+H+ ⇒ NO2 +H20
final reaction=
Sn + 4HNO3 SnO2 + 4 NO2 +2H20
0 +1+5-2 +4-2 +4-2
Charges on both the sides of reactant is
4 = 4
hence equation is balanced.
3 ) Voltaic cell and electrolyte cell difference is that voltaic cell converts chemical energy into electrical energy. Electrons are provided by redox reactions while in electrolyte cell electrical energy is converted to chemical energy and electron is given by external AC or DC battery.
Voltaic and electrolyte are similar as both these convert energy forms and require electron source for the reaction.