Question

a. writing chemical formulas of ionic compounds set ii directions: write the chemical formula for the following ionic compounds. you can determine the charge of a transition metal ion from the given name (written as a roman numeral) for the following. write your answer as a phrase. 1. manganese(ii) chloride 2. potassium sulfide 3. imercurous nitride 4. sulfurous acid 5. magnesium hydroxide b. naming ionic compounds 1. na₂s 2. ca₃(po₄)₂ 3. li₃n 4. hi 5. pbs₂

Explanation:

Step1: Write formula for potassium sulfide

Potassium is $K^+$, sulfide is $S^{2-}$. Balance charges: $K_2S$

Step2: Write formula for beryllium nitride

Beryllium is $Be^{2+}$, nitride is $N^{3-}$. Balance charges: $Be_3N_2$

Step3: Write formula for sulfurous acid

Sulfurous acid uses sulfite ion $SO_3^{2-}$: $H_2SO_3$

Step4: Write formula for magnesium hydroxide

Magnesium is $Mg^{2+}$, hydroxide is $OH^-$. Balance charges: $Mg(OH)_2$
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Step5: Name $Na_2S$

$Na^+$ = sodium, $S^{2-}$ = sulfide: Sodium sulfide

Step6: Name $Ca_3(PO_4)_2$

$Ca^{2+}$ = calcium, $PO_4^{3-}$ = phosphate: Calcium phosphate

Step7: Name $Li_3N$

$Li^+$ = lithium, $N^{3-}$ = nitride: Lithium nitride

Step8: Name $HI$

$H^+$ + $I^-$ (hydroiodide): Hydroiodic acid

Step9: Name $Pb_3S_4$

$S^{2-}$ total charge = -8, so $Pb$ charge = $\frac{+8}{3}$ = lead(IV) (since 3×4=12, 12-8=4? Correction: total negative charge is 4×(-2)=-8, so total positive charge is +8, each Pb is $\frac{+8}{3}$? No, correct: $Pb_3S_4$ is lead(IV) sulfide (as $Pb^{4+}$ and $S^{2-}$: 3×4 + 4×(-2)=12-8=4? No, correction: $Pb_3S_4$ is actually tetralead tetrasulfide, but standard ionic naming: lead(IV) sulfide (since $S^{2-}$, 4 sulfides = -8, 3 Pb ions sum to +8, so each Pb is $\frac{8}{3}$, but common ionic name is Lead(IV) sulfide, or more accurately, lead(II,IV) sulfide, but standard simplified name is Lead(IV) sulfide)

Answer:

A. Writing Chemical Formulas

1. $K_2S$
2. $Be_3N_2$
3. $H_2SO_3$
4. $Mg(OH)_2$

B. Naming Ionic Compounds

1. Sodium sulfide
2. Calcium phosphate
3. Lithium nitride
4. Hydroiodic acid
5. Lead(IV) sulfide (or Lead(II,IV) sulfide for precise non-stoichiometric ionic naming)