The acid  and alkali  that would react  to make sodium  sulfate is
alkali= sodium  hydroxide Â
acid = sulphuric acid
explanation
Acid react  react with alkali  to form salt  and  water.
For  sodium  sulfate salt to be  formed  a sulfate acid  is required to react  with a  hydroxide  of sodium .
 therefore Sodium hydroxide (alkali)  react with sulphuric acid (an acid)  to form sodium sulfate (salt) and water.
