Detailed Explanation:
1) Rusting of Iron
4Fe + 3O2 + 2H2O -> 2Fe2O32H2O
Reactants :-
Fe = 4
O = 3 * 2 + 2 = 8
H = 2 * 2 = 4
Products :-
Fe = 2 * 2 = 4
O = 2 * 3 + 2 = 8
H = 2 * 2 = 4
2) Fermentation of sucrose…
C12H22O11 + H2O -> 4C2H5OH + 4CO2
Reactants :-
C = 12
H = 22 + 2 = 24
O = 11 + 1 = 12
Products :-
C = 4 * 2 + 4 = 12
H = 4 * 5 + 4 = 24
O = 4 * 2 + 4 = 12
Looking closely at the way I have taken the total number of elements on the reactants and products side, you can solve the rest.
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are you sure it's Thaivan or Taiwan. If it's Taiwan than it's Taipei. 
     Hope this help :))
 
        
             
        
        
        
The triangle <span>in the first law of thermodynamics, represents energy that moves from a hot object to a cooler object.</span>
        
             
        
        
        
Answer:
Answers 2.( a) . (i)Total potential difference provided by the four cell = 4x 1.5 Volts = 6.0 Volts (ii)The component of X is a variable resistor . 
Explanation:
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