Which of the following correctly shows the formula for a hydrate?Multiple choice question.H2OMgSO4(H2O)7MgSO4•7H2OH2O2

Which of the following is correct with regard to hydrate?Select one:a.The numbers of mole of water in checmial formula of hydrates are always the same.b.Hydrate might have a different color from the anhydrous compound.c.Hydrate is a mixture of water and anhydrous salt.d.It is impossible to know the component of the anhydrous salt from the name of hydrate.

Which one of the following combinations of names and formulas of ions is incorrect?Group of answer choicesCN-  cyanideS2-  sulfate                           Ba2+  bariumClO4-  perchlorate

3. Choose the correct formula for hydroiodic acid.

Which one of the formulae below is the correct chemical formula for ammonium sulfate?Group of answer choices(a)   NH3SO4(b)   (NH3)2SO4(c)   NH4SO4(d)   NH4(SO4)2(e)   (NH4)2SO4

A chemical formula provides a shorthand representation of a compound's composition, indicating the elements present and the number of each type of atom. It is a concise way to understand a substance's makeup and predict its chemical interactions.Which of the following is not the correct chemical formula for the described compound?Group of answer choicesO2HCO2​NaClH2O