Naming Ionic Compounds Practice Worksheet | PDF - Free Printable

Here are the answers to your worksheet. I have worked through each one carefully to make sure the charges balance correctly for every compound.

Part 1: Name the following ionic compounds

To name these, we identify the positive ion (cation) first and the negative ion (anion) second. If the metal can have different charges (like Iron or Copper), we use Roman numerals to show which charge it has in that specific compound.

1) NH₄Cl
* Cation: NH₄⁺ is the ammonium ion.
* Anion: Cl⁻ is the chloride ion.
* Name: Ammonium chloride

2) Fe(NO₃)₃
* Anion: NO₃⁻ is nitrate. There are 3 nitrates, so the total negative charge is -3.
* Cation: To balance the -3, Iron (Fe) must be +3. So, this is Iron(III).
* Name: Iron(III) nitrate

3) TiBr₃
* Anion: Br⁻ is bromide. There are 3 bromides (-3 total).
* Cation: Titanium (Ti) must be +3 to balance it.
* Name: Titanium(III) bromide

4) Cu₃P
* Anion: P³⁻ is phosphide.
* Cation: There are 3 Copper atoms to balance the -3 charge. Each Copper must be +1.
* Name: Copper(I) phosphide

5) SnSe₂
* Anion: Se²⁻ is selenide. Two selenides make a -4 charge.
* Cation: Tin (Sn) must be +4 to balance it.
* Name: Tin(IV) selenide

6) GaAs
* Cation: Ga³⁺ is Gallium.
* Anion: As³⁻ is Arsenide.
* Name: Gallium arsenide

7) Pb(SO₄)₂
* Anion: SO₄²⁻ is sulfate. Two sulfates make a -4 charge.
* Cation: Lead (Pb) must be +4 to balance it.
* Name: Lead(IV) sulfate

8) Be(HCO₃)₂
* Cation: Be²⁺ is Beryllium.
* Anion: HCO⁻ is bicarbonate (or hydrogen carbonate).
* Name: Beryllium bicarbonate

9) Mn₂(SO₃)₃
* Anion: SO₃²⁻ is sulfite. Three sulfites make a -6 charge.
* Cation: Two Manganese atoms must equal +6. So each Mn is +3.
* Name: Manganese(III) sulfite

10) Al(CN)₃
* Cation: Al³⁺ is Aluminum.
* Anion: CN⁻ is cyanide.
* Name: Aluminum cyanide

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Part 2: Write the formulas for the following compounds

To write these, we look at the charge of the cation and the anion. We swap the numbers (cross-over method) to make sure the total positive charge equals the total negative charge.

11) chromium (VI) phosphate
* Chromium(VI) is Cr⁶⁺.
* Phosphate is PO₄³⁻.
* To balance +6 and -3, we need two phosphates (-6) for every one chromium (+6).
* Formula: Cr(PO₄)₂

12) vanadium (IV) carbonate
* Vanadium(IV) is V⁴⁺.
* Carbonate is CO₃²⁻.
* To balance +4 and -2, we need two carbonates (-4) for every one vanadium (+4).
* Formula: V(CO₃)₂

13) tin (II) nitrite
* Tin(II) is Sn²⁺.
* Nitrite is NO₂⁻.
* To balance +2 and -1, we need two nitrites.
* Formula: Sn(NO₂)₂

14) cobalt (III) oxide
* Cobalt(III) is Co³.
* Oxide is O²⁻.
* The least common multiple of 3 and 2 is 6. We need two Co³⁺ (+6) and three O²⁻ (-6).
* Formula: Co₂O₃

15) titanium (II) acetate
* Titanium(II) is Ti²⁺.
* Acetate is C₂HO₂⁻ (sometimes written as CHCOO⁻).
* To balance +2 and -1, we need two acetates.
* Formula: Ti(C₂HO₂)₂

16) vanadium (V) sulfide
* Vanadium(V) is V⁵⁺.
* Sulfide is S²⁻.
* The least common multiple of 5 and 2 is 10. We need two V⁵⁺ (+10) and five S²⁻ (-10).
* Formula: V₂S₅

17) chromium (III) hydroxide
* Chromium(III) is Cr³⁺.
* Hydroxide is OH⁻.
* To balance +3 and -1, we need three hydroxides.
* Formula: Cr(OH)₃

18) lithium iodide
* Lithium is Li⁺.
* Iodide is I⁻.
* They balance 1-to-1.
* Formula: LiI

19) lead (II) nitride
* Lead(II) is Pb²⁺.
* Nitride is N³⁻.
* The least common multiple of 2 and 3 is 6. We need three Pb²⁺ (+6) and two N³⁻ (-6).
* Formula: Pb₃N₂

20) silver bromide
* Silver is always Ag⁺.
* Bromide is Br⁻.
* They balance 1-to-1.
* Formula: AgBr

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Final Answer:

Naming Ionic Compounds:
1) Ammonium chloride
2) Iron(III) nitrate
3) Titanium(III) bromide
4) Copper(I) phosphide
5) Tin(IV) selenide
6) Gallium arsenide
7) Lead(IV) sulfate
8) Beryllium bicarbonate
9) Manganese(III) sulfite
10) Aluminum cyanide

Writing Formulas:
11) Cr(PO₄)₂
12) V(CO₃)₂
13) Sn(NO₂)₂
14) Co₂O₃
15) Ti(C₂H₃O₂)₂
16) V₂S₅
17) Cr(OH)₃
18) LiI
19) Pb₃N₂
20) AgBr