Question

These questions will help you with your own data collection 1. What is the molar mass of cupric sulfate pentahydrate? (CuSO4.5H20) 2. How many grams of CuSO4.5H2O is needed to make a 0.1 M solution in 40 mL of water? 3. If you wanted to make 10 mL of a 0.06 M CuSO4 solution, what ml amount of 0.1 M CuSO4 solution and deionized water would you need? (Remember: M,V=MV)

Answer 1

1. The Molar mass of $CuSO_{4}.5H_{2}O$ is

249.68g/, mol

2. Now, let us determine the number of moles in 40 mL of 0.1 M solution as below-

maler Cusou 5t20 40 mL omoler malen Cu Soy. 5t20 1 L 40 mL mdles mmd Cusou.st20 2 25 Cm Cusou SH20
hence the amount of $CuSO_{4}.5H_{2}O$ required = $0.004mol\times 249.68(g/mol)=0.99g$ to prepare 40mL of 0.1 M solution.

3. Applying the $V_{1}S_{1}=V_{2}S_{2}$ rule, where

$V_{1}=$ 10 mL, $S_{1}=0.06M$ , $V_{2}=?$ , $S_{2}=0.1$

Hence, $V_{2}=V_{1}S_{1}/S_{2}$ =$(10\times 0.06)/0.1=6mL$ of 0.1 M CuSO4 aqueous solution needed.