Question

practice: ions, cations, anions & polyatomic ions
part a: identify the type
directions: write cation, anion, or polyatomic ion.

1. $na^{+}$ _______________
2. $cl^{-}$ _______________
3. $nh_{4}^{+}$ _______________
4. $so_{4}^{2-}$ _______________
5. $ca^{2+}$ _______________
6. $no_{3}^{-}$ _______________

part b: determine the charge
directions: circle whether each ion is positive (+) or negative (-).

1. $al^{3+}$ (+ / -)
2. $o^{2-}$ (+ / -)
3. $k^{+}$ (+ / -)
4. $co_{3}^{2-}$ (+ / -)

part c: ionic or not?
directions: decide whether each compound is ionic.

1. $nano_{3}$ _______________
2. $h_{2}o$ _______________
3. $caco_{3}$ _______________
4. $nh_{4}cl$ _______________

Explanation:

Part A: Cations are positively charged single ions, anions are negatively charged single ions, polyatomic ions are charged groups of multiple atoms.
Part B: The superscript symbol indicates charge: + is positive, - is negative.
Part C: Ionic compounds form between cations (metal or polyatomic positive) and anions (nonmetal or polyatomic negative); non-ionic are molecular (nonmetal-nonmetal, no ion pairing).

Answer:

Part A: Identify the Type

1. $\text{Na}^+$: cation
2. $\text{Cl}^-$: anion
3. $\text{NH}_4^+$: polyatomic ion
4. $\text{SO}_4^{2-}$: polyatomic ion
5. $\text{Ca}^{2+}$: cation
6. $\text{NO}_3^-$: polyatomic ion

Part B: Determine the Charge

1. $\text{Al}^{3+}$: (+)
2. $\text{O}^{2-}$: (-)
3. $\text{K}^+$: (+)
4. $\text{CO}_3^{2-}$: (-)

Part C: Ionic or Not?

1. $\text{NaNO}_3$: Ionic
2. $\text{H}_2\text{O}$: Not ionic
3. $\text{CaCO}_3$: Ionic
4. $\text{NH}_4\text{Cl}$: Ionic