Question

hi, Just want to ask how to define the term 'formula unit'.
Consider CuSO4．5H2O, what is the formula unit and the number of formula unit?

Answer 1

"formula unit" is another way of saying "molecule", and is used primarily when describing ionic crystals. Since ionic substances (like salt) are big collections of alternating positive and negative charges stretching in all directions, the word "molecule" doesn't really apply. So we use the term "formula unit" to describe the smallest possible piece of an ionic crystal. In this case, the formula CuSO4*5H2O is one formula unit of the hydrate copper (II) sulfate pentahydrate. There is 1 formula unit of copper (II) sulfate and 5 molecules of water that make up one formula unit of the hydrate

Answer 2

so the formula unit is 1?

Answer 3

the formula unit is one copy of that formula, so yes.

Answer 4

Thank you !!!!!