okk heres the summary first..
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2NaOH + H2SO4 --> Na2SO4 + H2O
(26.2 cm3) (25cm3)
(0.1 mol/dm3) _____(watever doesnt matter)
0.00262 moles 0.00131 moles
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ok now,
we know that 25 cm3 of acid is 0.00131 moles....
they are just asking what no. of moles will react with 250 cm3..
therefore 25cm3 - 0.00131 moles
250cm3 - 0.00131 moles * 10 = 0.0131 (ANSWER!!!)
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some1 plz correct the method if wrong...