[Ann28]

Could anyone clarify this. I was reading through an article which stated that phosphorus or phosphate concentrations measured in mmol/L are the same but not when expressed in mg/dl. For example, a phosphorus concentration of 5mmol/L is equivalent to a phosphate concentration of 5mmol/L. But 5mg/dl of phosphate is about 3.1 times the concentration of phosphorus in mg/dl.

[fledarmus]

Do you know how to calculate the number of moles of a compound given the number of grams? Or vice versa?

That statement is like saying that the amount of cars and eggs that you have are the same when expressed in dozens, but not when expressed in tons.