Answer:
4.
You see, 2 atoms of O in the CO₂ and 2 O in the 2 moles of H₂O
Explanation:
CH₄ + 2O₂ → CO₂ + 2H₂O
Answer : The current passing between the electrodes is, 
Explanation :
First we have to calculate the charge of sodium ion.

where,
q = charge of sodium ion
n = number of sodium ion = 
e = charge on electron = 
Now put all the given values in the above formula, we get:

Now we have to calculate the charge of chlorine ion.

where,
q' = charge of chlorine ion
n = number of chlorine ion = 
e = charge on electron = 
Now put all the given values in the above formula, we get:

Now we have to calculate the current passing between the electrodes.



Thus, the current passing between the electrodes is, 
Answer: Charles's law, Avogadro's law and Boyle's law.
Justification:
Boyle's law states that at constant temperature PV = constant
Charles law states that at constant pressure V/T = constant
Avogadro's law states that at constant pressure ant temperature, equal volume of gases contain equal number of moles: V/n = constant
Ideal gas law states PV/nT = constant => PV = nT*constant = PV = nTR
Answer : The value of
for this reaction is 36.18 kJ
Explanation :
First law of thermodynamic : It states that the energy can not be created or destroyed, it can only change or transfer from one state to another state.
As per first law of thermodynamic,

where,
= internal energy of the system
q = heat added or rejected by the system
w = work done
As we are given that:
q = 38.65 kJ
w = -2.47 kJ (system work done on surrounding)
Now put all the given values in the above expression, we get:


Therefore, the value of
for this reaction is 36.18 kJ