Whats the method?
Can you post the working
Later in the day
First 1 mmole of NaHCO3 is formed
Then reaction with 0.25 mmole HCl gives 0.25 mole H2CO3 and 0.75 mmole NaHCO3 remains.
then use buffer formula using pka as only first value.
(though i am not entirely convinced of my approximation and I may be wrong as the answer is not known so feel free to correct me)
Actually I wasn't sure if this happens. Thanks.
Assuming my answer is correct, don't thank me too soon, why were you thinking that might not happen? could be an issue
I wasn't sure if the second reaction would go towards completion or it would be a reversible one.
But its a basic salt with a strong acid so I think it will go towards completion and your answer is correct.