Question

Number of hydrogen-bonded water molecules associated in $CuS{O}_4.5H_{2}O$ is :

• A. One
• B. Two
• C. Three
• D. All the five

Answer 1

Answer: (A)

One

In $CuS{O}_4.5H_{2}O,Cu$ is coordinated with 4 water molecules and two more oxygen atoms from Sulphate ion.

Now fifth water molecule is hydrogen-bonded and is deeply embedded in a crystal. It is not coordinated.

Only 4 water molecules are coordinated and the fifth is the only hydrogen bonded.

Hence, option $A$ is correct.