A chemist prepares a solution of silver (I) nitrate by measuring out of silver (I) nitrate into a volumetric flask and filling the flask to the mark with water.

3.33 M

Explanation:

It seems your question is incomplete, however, that same fragment has been found somewhere else in the web:

" A chemist prepares a solution of silver nitrate (AgNO3) by measuring out 85. g of silver nitrate into a 150. mL volumetric flask and filling the flask to the mark with water.

Calculate the concentration in mol/L of the chemist's silver nitrate solution. Be sure your answer has the correct number of significant digits. "

In this case, first we calculate the moles of AgNO₃, using its molecular weight:

85.0 g AgNO₃ : 169.87 g/mol = 0.500 mol AgNO₃

Then we convert the 150 mL of the volumetric flask into L:

150 / 1000 = 0.150 L

Finally we divide the moles by the volume:

0.500 mol AgNO₃ / 0.150 L = 3.33 M