Chemistry worksheet on naming and formulas of ionic compounds with an included answer key.

Here are the solutions to the chemistry worksheet problems, organized by section.

Section 1: Naming Ionic Compounds

Task: Write the name of each compound.
Rule: Name the metal first (unchanged), then the non-metal with an "-ide" ending.

1. KCl: Potassium (K) + Chlorine (Cl) $\rightarrow$ Potassium chloride
2. AlI$_3$: Aluminum (Al) + Iodine (I) $\rightarrow$ Aluminum iodide
3. CaF$_2$: Calcium (Ca) + Fluorine (F) $\rightarrow$ Calcium fluoride
4. BaO: Barium (Ba) + Oxygen (O) $\rightarrow$ Barium oxide
5. Ba$_3$N$_2$: Barium (Ba) + Nitrogen (N) $\rightarrow$ Barium nitride
6. Al$_2$Se$_3$: Aluminum (Al) + Selenium (Se) $\rightarrow$ Aluminum selenide
7. Ga$_4$C$_3$: Gallium (Ga) + Carbon (C) $\rightarrow$ Gallium carbide
8. Mg$_2$Si: Magnesium (Mg) + Silicon (Si) $\rightarrow$ Magnesium silicide
9. Li$_3$N: Lithium (Li) + Nitrogen (N) $\rightarrow$ Lithium nitride
10. Na$_4$C: Sodium (Na) + Carbon (C) $\rightarrow$ Sodium carbide

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Section 2: Writing Formulas for Ionic Compounds

Task: Write the formula of each compound.
Rule: Balance the charges so the total is zero. Use the periodic table to find the charge for each ion (Group 1 = +1, Group 2 = +2, Group 13 = +3, Group 15 = -3, Group 16 = -2, Group 17 = -1).

11. Sodium Hydride:
* Sodium ($Na^+$) has a +1 charge.
* Hydride ($H^-$) has a -1 charge.
* They balance 1:1.
* Formula: NaH

12. Aluminum Oxide:
* Aluminum ($Al^{3+}$) has a +3 charge.
* Oxide ($O^{2-}$) has a -2 charge.
* Least common multiple is 6. Need two $Al^{3+}$ (+6) and three $O^{2-}$ (-6).
* Formula: Al$_2$O$_3$

13. Calcium Phosphide:
* Calcium ($Ca^{2+}$) has a +2 charge.
* Phosphide ($P^{3-}$) has a -3 charge.
* Least common multiple is 6. Need three $Ca^{2+}$ (+6) and two $P^{3-}$ (-6).
* Formula: Ca$_3$P$_2$

14. Potassium Sulfide:
* Potassium ($K^+$) has a +1 charge.
* Sulfide ($S^{2-}$) has a -2 charge.
* Need two $K^+$ (+2) to balance one $S^{2-}$ (-2).
* Formula: K$_2$S

15. Barium Chloride:
* Barium ($Ba^{2+}$) has a +2 charge.
* Chloride ($Cl^-$) has a -1 charge.
* Need one $Ba^{2+}$ (+2) and two $Cl^-$ (-2).
* Formula: BaCl$_2$

16. Gallium Fluoride:
* Gallium ($Ga^{3+}$) has a +3 charge.
* Fluoride ($F^-$) has a -1 charge.
* Need one $Ga^{3+}$ (+3) and three $F^-$ (-3).
* Formula: GaF$_3$

17. Beryllium iodide:
* Beryllium ($Be^{2+}$) has a +2 charge.
* Iodide ($I^-$) has a -1 charge.
* Need one $Be^{2+}$ (+2) and two $I^-$ (-2).
* Formula: BeI$_2$

18. Indium Arsenide:
* Indium ($In^{3+}$) has a +3 charge.
* Arsenide ($As^{3-}$) has a -3 charge.
* Charges cancel out 1:1.
* Formula: InAs

19. Germanium Oxide:
* Germanium ($Ge^{4+}$) has a +4 charge.
* Oxide ($O^{2-}$) has a -2 charge.
* Need one $Ge^{4+}$ (+4) and two $O^{2-}$ (-4).
* Formula: GeO$_2$

20. Beryllium Sulfide:
* Beryllium ($Be^{2+}$) has a +2 charge.
* Sulfide ($S^{2-}$) has a -2 charge.
* Charges cancel out 1:1.
* Formula: BeS

Final Answer:
Section 1 Answers:
1) Potassium chloride
2) Aluminum iodide
3) Calcium fluoride
4) Barium oxide
5) Barium nitride
6) Aluminum selenide
7) Gallium carbide
8) Magnesium silicide
9) Lithium nitride
10) Sodium carbide

Section 2 Answers:
11) NaH
12) Al$_2$O$_3$
13) Ca$_3$P$_2$
14) K$_2$S
15) BaCl$_2$
16) GaF$_3$
17) BeI$_2$
18) InAs
19) GeO$_2$
20) BeS