Question

name the following hydrates

1. cr₂(co₃)₃•h₂o
2. caso₄•2h₂o
3. fepo₄•3h₂o

give the formulas for the following hydrates:

1. cupric sulfite pentahydrate
2. cobalt(iii) carbonate tetrahydrate

name the following compounds (mixed types):

1. pbs
2. icl
3. h₂c₂o₄(aq)
4. cu₃(po₄)₂
5. p₄h₁₀
6. mgso₄•7h₂o
7. li₂co₃

give formulas for the following compounds (mixed types)

1. stannous fluoride
2. hydroiodic acid
3. sodium carbonate dihydrate
4. sulfur hexaiodide
5. mercurous nitrite
6. potassium permanganate
7. oxygen dichloride

Explanation:

Step1: Name $Cr_2(CO_3)_3\cdot H_2O$

The cation is chromium(III) as chromium has a +3 charge to balance the - 2 charge of carbonate ($CO_3^{2 -}$) and there are 3 carbonate groups. The hydrate has 1 water molecule, so it is called chromium(III) carbonate monohydrate.

Step2: Name $CaSO_4\cdot 2H_2O$

The cation is calcium and the anion is sulfate. It has 2 water molecules, so it is called calcium sulfate dihydrate.

Step3: Name $FePO_4\cdot 3H_2O$

The cation is iron(III) (since phosphate has a - 3 charge) and the anion is phosphate. With 3 water molecules, it is called iron(III) phosphate trihydrate.

Step4: Write formula for cupric sulfite pentahydrate

Cupric means copper(II), sulfite is $SO_3^{2 -}$. So the formula is $CuSO_3\cdot 5H_2O$.

Step5: Write formula for cobalt(III) carbonate tetrahydrate

Cobalt(III) is $Co^{3+}$ and carbonate is $CO_3^{2 -}$. The formula is $Co_2(CO_3)_3\cdot 4H_2O$.

Step6: Name $PbS$

The cation is lead(II) and the anion is sulfide, so it is called lead(II) sulfide.

Step7: Name $ICl$

It is a binary covalent compound. Named as iodine monochloride.

Step8: Name $H_2C_2O_4(aq)$

It is an acid. The anion is oxalate, so it is called oxalic acid.

Step9: Name $Cu_3(PO_4)_2$

The cation is copper(II) and the anion is phosphate, so it is called copper(II) phosphate.

Step10: Name $P_4H_{10}$

It is a binary covalent compound. Named as tetraphosphorus decahydride.

Step11: Name $MgSO_4\cdot 7H_2O$

The cation is magnesium and the anion is sulfate. With 7 water molecules, it is called magnesium sulfate heptahydrate.

Step12: Name $Li_2CO_3$

The cation is lithium and the anion is carbonate, so it is called lithium carbonate.

Step13: Write formula for stannous fluoride

Stannous means tin(II), fluoride is $F^-$. The formula is $SnF_2$.

Step14: Write formula for hydroiodic acid

The formula for hydroiodic acid is $HI$.

Step15: Write formula for sodium carbonate dihydrate

Sodium is $Na^+$, carbonate is $CO_3^{2 -}$. The formula is $Na_2CO_3\cdot 2H_2O$.

Step16: Write formula for sulfur hexaiodide

The formula is $SI_6$.

Step17: Write formula for mercurous nitrite

Mercurous means mercury(I) ($Hg_2^{2+}$), nitrite is $NO_2^-$. The formula is $Hg_2(NO_2)_2$.

Step18: Write formula for potassium permanganate

Potassium is $K^+$ and permanganate is $MnO_4^-$. The formula is $KMnO_4$.

Step19: Write formula for oxygen dichloride

The formula is $OCl_2$.

Answer:

1. Chromium(III) carbonate monohydrate
2. Calcium sulfate dihydrate
3. Iron(III) phosphate trihydrate
4. $CuSO_3\cdot 5H_2O$
5. $Co_2(CO_3)_3\cdot 4H_2O$
6. Lead(II) sulfide
7. Iodine monochloride
8. Oxalic acid
9. Copper(II) phosphate
10. Tetraphosphorus decahydride
11. Magnesium sulfate heptahydrate
12. Lithium carbonate
13. $SnF_2$
14. $HI$
15. $Na_2CO_3\cdot 2H_2O$
16. $SI_6$
17. $Hg_2(NO_2)_2$
18. $KMnO_4$
19. $OCl_2$