Question

5) Calculate the number of grams of solute in 500.0 mL of 0.179 M KOH.

A) 157 g B) 1.60 g C) 5.02 × 103 g D) 1.60 × 10-3 g E) 5.02 g

Answer 1

Hey there!:

Molar mass KOH = 56.1056 g/mol

Volume in liters of solution :

500.0 mL / 1000 => 0.5 L

Number of moles :

moles = M * V

moles  = 0.179 * 0.5

moles =  0.0895 moles of KOH

Therefore:

1 mol KOH ------------------------ 56.1056 g

0.0895 moles KOH -------------  ( mass of KOH ) ??

mass of KOH = 0.0895 * 56.1056

mass of KOH = 5.02 g

Answer E

Hope this helps!