Answer
$104.03\ g/mol$
Work Step by Step
Number of moles of the base:
$0.509\ M\times 36.04\ mL=18.34\ mmol$
From stoichiometry:
$9.17\ mmol$ of acid.
Molar mass:
$954\ mg\div 9.17\ mmol=104.03\ g/mol$
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.