Use the formula for second order reaction:

C = concentration at time t
C0 = initial conc.
k = rate constant
t = time
1st equation :

2nd Equation:

Find

from 1st equation and put it in 2nd equation:


k = 0.046
The equation is H2SO4 + 2NaOH = 2H2O + Na2SO4, Also, what is the theoretical yield of Na2SO4 in grams?
Answer : The number of moles of
produced from the reaction is, 14 moles
Explanation :
The given balanced reaction is,

By the stoichiometry, 1 mole of cesium fluoride react with the 1 mole of xenon hexafluoride to give 1 mole of cesium xenon heptafluoride.
That means the mole ratio of 
As 14 moles of cesium fluoride react with the 14 moles of xenon hexafluoride to give 14 moles of cesium xenon heptafluoride.
Hence, the number of moles of
produced from the reaction is, 14 moles