Answer
Please see the work below.
Work Step by Step
We know that
$molarity=\frac{moles \space of\space solute }{Liters \space of \space solution}$
$molartiy=\frac{0.024502\space mol\space Na_2SO_4 }{0.0250L}=0.9801M$
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.