Answer:
a. .125 mol b. 7.25g
Explanation:
a. To get the moles multiply the volume by the molarity.
.5L*.25M=.125mol NaCl
b. The molar mass is provided so multiply the moles by the molar mass to get the amount of grams of nacl.
.125mol*58molar mass=7.25g nacl to make the solution