# how does sulphuric acid both be needed for hydrolysing and forming starch? [closed]

I apologize if the question sounds weird. I'm in grade 10, and we were doing esters for organic chemistry. one needs sulphuric acid as a catalyst for the formation of esters...apparently due to it being a dehydrating agent. So....how does it hydrolysed...please someone explain this to me. While we're on this I read that sodium hydroxide can also break down an ester into its component parts...which is also hydrolysis. can we also hydrolyse starch by using sodium hydroxide?

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• Starch does not have ester groups but rather acetal linkages. While esters hydrolyze in aqueous acid or base, acetals are stable to aqueous base and labile to aqueous mineral acid. – user55119 Feb 20 at 17:29

the main interest of sulfuric acid in ester synthesis is to provide the catalyst $$\ce {H_3O^+}$$;