6 separate questions. I have figured out the other 20 questions I am stuck. Please help Thanks

Question

The correct name for the ionic compound Al2Se3 is?

The correct name for the ionic compound
Fe2Se3 is?

the Roman numerall III in the name Iron(III)oxice indicates what?

Which of the following compounds contains four atoms per formula unit? please Explain and show
a. chrominum(III)nitride
b. tin(II)iodide
c. magnesium floride
d. ruthenium(III)chloride

The formulas of the sulfate ion, the nitrate ion, and the phosphate ion are, respectively:

which of the following compounds has a formula that contains parentheses?
a. barium carbonate
b. lithium hydroxide
c. strontium hydroxide
d. ammonium hydroxide

Answer 1

The correct name for the ionic compound Al2Se3 is?
I would name this aluminum selenide but some might prefer the name aluminum triselenide.

The correct name for the ionic compound
Fe2Se3 is?
I would name this iron(III) selenide; some may prefer iron(III) triselenide.

the Roman numerall III in the name Iron(III)oxice indicates what?
The (III) indicates that the iron has an oxidation state of III (as opposed to II or some other number).

Which of the following compounds contains four atoms per formula unit? please Explain and show
a. chrominum(III)nitride
b. tin(II)iodide
c. magnesium floride
d. ruthenium(III)chloride
The formulas are
a. CrN = 2 atoms/formula unit.
b. SnI2 = 3 atoms/formula unit
c. MgF2 = 3 atoms/formula unit
d. RhCl3 = 4 atoms/formula unit


The formulas of the sulfate ion, the nitrate ion, and the phosphate ion are, respectively:

sulfate is SO4^2-
nitrate is NO3^-
phosphate is PO4^3-

which of the following compounds has a formula that contains parentheses?
a. barium carbonate
b. lithium hydroxide
c. strontium hydroxide
d. ammonium hydroxide
The formulas are
BaCO3
Li(OH)2
Sr(OH)2
NH4OH

Answer 2

Iron(III) selenide
It indicates the ion Fe is a Plus 3 valence
chromiumIIInitride CrN3
-2, -1, -3 You really ought to be memorizing these.

Sr(OH)2