Stoichiometry

(100 * 0.1) = ( 0.25 * v)/2
=>20/0.25 =v =80ml

the main prob i suppose will be in judging eq wt of NaAl(OH)2CO3
which is 1
becoz Na⁺ and (Al³⁺(OH^-)₂CO₃^2-)^-

*edit :its not eq wt as i wrote...its n factor *

if in a balanced chemical equation , we find x* acid + y* base gives the correct balance, then
V₁M₁ / X = V₂M₂ / Y
(M-MOLARITY )

answer should be 160ml naa!!!!

n-factor of given compound is 4
so by eq.concept
100*0.1*4=0.25*V
V=160ml

No decoder I guess n - factor is 1

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as eureka said Na+ & ...

Answer is 80 mL

so thats the process !