Find the pH of resultant solution when 100 mL of 0.005 M H_(2)SO_(4) " at " 25^(@)C is diluted to 1000 mL. What is the amount of NaOH required to be dissolved in 500 mL to exactly neutralise the above solution ?

Find the pH of resultant solution when 100 mL of 0.005 M H_(2)SO_(4) "

1.	Find the pH of resultant solution when 100 mL of 0.005 M H_(2)SO_(4) " at " 25^(@)C is diluted to 1000 mL. What is the amount of NaOH required to be dissolved in 500 mL to exactly neutralise the above solution ?
Answer» Solution :Normality of `H_(2)SO_(4)` = MOLARITY `xx 2 = 0.005 xx 2 = 0.01` According to dilution law `100 xx 0.01 = 1000 xx x` `= (100 xx 0.01)/(1000) = 0.001 = 1 xx 10^(-3)` `pH = - "log" 1xx 10^(-3) = 3` If this solution neutralised by 500 ML of NaOH solution. `100 xx 10^(-3) = 500 xx c` `c = 2 xx 10^(-3)` Amount of NaOH required `2 xx 10^(-3) = (9x)/(40) xx (1000)/(500)` `2 xx 10^(-3) xx 40//2= 4 xx 10^(-2) g`