Question

ws 5h, ionic compounds w/polyatomic ions
common polyatomic ions
name\tformula
ammonium\tnh₄⁺¹
hydroxide\toh⁻¹
sulfite\tso₃⁻²
sulfate\tso₄⁻²
nitrite\tno₂⁻¹
nitrate\tno₃⁻¹
carbonate\tco₃⁻²
phosphate\tpo₄⁻³
directions:
a. write the proper names for each of the following ionic compounds having polyatomic ions.
a. caco₃\tb. li₂so₄
c. alpo₄\td. mgno₃
e. cr(so₄)₂\tf. al(no₂)₃
g. fe₃(po₄)₂\th. naoh
i. (nh₄)₃po₄\tj. k₂so₃
-continue on back-
b. write the proper formulas for each of the following ionic compounds having polyatomic ions.
a. barium nitrate\tb. ammonium hydroxide
c. calcium phosphate\td. cobalt (iv) phosphide
e. chromium (v) sulfate\tf. vanadium (iii) fluoride
g. aluminum nitrite\th. potassium hydroxide
i. lithium phosphate\tk. copper (ii) sulfite

Answer:

Part A: Naming Ionic Compounds with Polyatomic Ions

a. $\ce{CaCO_{3}}$

Step1: Identify cation and polyatomic ion

Cation: $\ce{Ca^{2+}}$ (calcium), Polyatomic ion: $\ce{CO_{3}^{2-}}$ (carbonate)

Step2: Combine names

Name: Calcium Carbonate

b. $\ce{Li_{2}SO_{4}}$

Step1: Identify cation and polyatomic ion

Cation: $\ce{Li^{+}}$ (lithium), Polyatomic ion: $\ce{SO_{4}^{2-}}$ (sulfate)

Step2: Combine names (balance charges: 2 $\ce{Li^{+}}$ for 1 $\ce{SO_{4}^{2-}}$)

Name: Lithium Sulfate

c. $\ce{AlPO_{4}}$

Step1: Identify cation and polyatomic ion

Cation: $\ce{Al^{3+}}$ (aluminum), Polyatomic ion: $\ce{PO_{4}^{3-}}$ (phosphate)

Step2: Combine names (charges balance 1:1)

Name: Aluminum Phosphate

d. $\ce{MgNO_{3}}$ (Note: Correct formula should be $\ce{Mg(NO_{3})_{2}}$ for charge balance, but assuming given formula)

Step1: Identify cation and polyatomic ion

Cation: $\ce{Mg^{2+}}$ (magnesium), Polyatomic ion: $\ce{NO_{3}^{-}}$ (nitrate)

Step2: Combine names (assuming formula is as given, though charge balance is off)

Name: Magnesium Nitrate (Correct formula: $\ce{Mg(NO_{3})_{2}}$)

e. $\ce{Cr(SO_{4})_{2}}$

Step1: Identify cation and polyatomic ion

Cation: $\ce{Cr^{4+}}$ (chromium(IV)), Polyatomic ion: $\ce{SO_{4}^{2-}}$ (sulfate) (2 sulfates for 1 $\ce{Cr^{4+}}$)

Step2: Combine names

Name: Chromium(IV) Sulfate

f. $\ce{Al(NO_{2})_{3}}$

Step1: Identify cation and polyatomic ion

Cation: $\ce{Al^{3+}}$ (aluminum), Polyatomic ion: $\ce{NO_{2}^{-}}$ (nitrite) (3 nitrites for 1 $\ce{Al^{3+}}$)

Step2: Combine names

Name: Aluminum Nitrite

g. $\ce{Fe_{3}(PO_{4})_{2}}$

Step1: Identify cation and polyatomic ion

Cation: $\ce{Fe^{2+}}$ (iron(II)) (3 $\ce{Fe^{2+}}$ for 2 $\ce{PO_{4}^{3-}}$: 3×2=6, 2×3=6), Polyatomic ion: $\ce{PO_{4}^{3-}}$ (phosphate)

Step2: Combine names

Name: Iron(II) Phosphate

h. $\ce{NaOH}$

Step1: Identify cation and polyatomic ion

Cation: $\ce{Na^{+}}$ (sodium), Polyatomic ion: $\ce{OH^{-}}$ (hydroxide)

Step2: Combine names

Name: Sodium Hydroxide

i. $\ce{(NH_{4})_{3}PO_{4}}$

Step1: Identify cation and polyatomic ion

Cation: $\ce{NH_{4}^{+}}$ (ammonium) (3 ammoniums for 1 $\ce{PO_{4}^{3-}}$), Polyatomic ion: $\ce{PO_{4}^{3-}}$ (phosphate)

Step2: Combine names

Name: Ammonium Phosphate

j. $\ce{K_{2}SO_{3}}$

Step1: Identify cation and polyatomic ion

Cation: $\ce{K^{+}}$ (potassium) (2 $\ce{K^{+}}$ for 1 $\ce{SO_{3}^{2-}}$), Polyatomic ion: $\ce{SO_{3}^{2-}}$ (sulfite)

Step2: Combine names

Name: Potassium Sulfite

Part B: Writing Formulas for Ionic Compounds with Polyatomic Ions

a. Barium Nitrate

Step1: Identify ions

Cation: $\ce{Ba^{2+}}$ (barium), Polyatomic ion: $\ce{NO_{3}^{-}}$ (nitrate)

Step2: Balance charges (1 $\ce{Ba^{2+}}$ needs 2 $\ce{NO_{3}^{-}}$)

Formula: $\ce{Ba(NO_{3})_{2}}$

b. Ammonium Hydroxide

Step1: Identify ions

Cation: $\ce{NH_{4}^{+}}$ (ammonium), Polyatomic ion: $\ce{OH^{-}}$ (hydroxide)

Step2: Balance charges (1:1)

Formula: $\ce{NH_{4}OH}$ (or $\ce{NH_{3}\cdot H_{2}O}$, but ionic formula: $\ce{NH_{4}OH}$)

c. Calcium Phosphate

Step1: Identify ions

Cation: $\ce{Ca^{2+}}$ (calcium), Polyatomic ion: $\ce{PO_{4}^{3-}}$ (phosphate)

Step2: Balance charges (3 $\ce{Ca^{2+}}$ for 2 $\ce{PO_{4}^{3-}}$: 3×2=6, 2×3=6)

Formula: $\ce{Ca_{3}(PO_{4})_{2}}$

d. Cobalt(IV) Phosphide (Note: Phosphide is $\ce{P^{3-}}$, not polyatomic, but included)

Step1: Identify ions

Cation: $\ce{Co^{4+}}$ (cobalt(IV)), Anion: $\ce{P^{3-}}$ (phosphide)

Step2: Balance charges (3 $\ce{Co^{4+}}$ for 4 $\ce{P^{3-}}$: 3×4=12, 4×3=12)

Formula: $\ce{Co_{3}P_{4}}$

e. Chromium(V) Sulfate

Step1: Identify ions

Cation: $\ce{Cr^{5+}}$ (chromium(V)), Polyatomic ion: $\ce{SO_{4}^{2-}}$ (sulfate)

Step2: Balance charges (2 $\ce{Cr^{5+}}$ for 5 $\ce{SO_{4}^{2-}}$: 2×5=10, 5×2=10)

Formula: $\ce{Cr_{2}(SO_{4})_{5}}$

f. Vanadium(III) Fluoride (Fluoride is $\ce{F^{-}}$, not polyatomic)

Step1: Identify ions

Cation: $\ce{V^{3+}}$ (vanadium(III)), Anion: $\ce{F^{-}}$ (fluoride)

Step2: Balance charges (1 $\ce{V^{3+}}$ needs 3 $\ce{F^{-}}$)

Formula: $\ce{VF_{3}}$

g. Aluminum Nitrite

Step1: Identify ions

Cation: $\ce{Al^{3+}}$ (aluminum), Polyatomic ion: $\ce{NO_{2}^{-}}$ (nitrite)

Step2: Balance charges (1 $\ce{Al^{3+}}$ needs 3 $\ce{NO_{2}^{-}}$)

Formula: $\ce{Al(NO_{2})_{3}}$

h. Potassium Hydroxide

Step1: Identify ions

Cation: $\ce{K^{+}}$ (potassium), Polyatomic ion: $\ce{OH^{-}}$ (hydroxide)

Step2: Balance charges (1:1)

Formula: $\ce{KOH}$

i. Lithium Phosphate

Step1: Identify ions

Cation: $\ce{Li^{+}}$ (lithium), Polyatomic ion: $\ce{PO_{4}^{3-}}$ (phosphate)

Step2: Balance charges (3 $\ce{Li^{+}}$ for 1 $\ce{PO_{4}^{3-}}$)

Formula: $\ce{Li_{3}PO_{4}}$

k. Copper(II) Sulfite

Step1: Identify ions

Cation: $\ce{Cu^{2+}}$ (copper(II)), Polyatomic ion: $\ce{SO_{3}^{2-}}$ (sulfite)

Step2: Balance charges (1:1)

Formula: $\ce{CuSO_{3}}$

Final Answers (Summarized)

Part A:

a. Calcium Carbonate
b. Lithium Sulfate
c. Aluminum Phosphate
d. Magnesium Nitrate (Note: Correct formula should be $\ce{Mg(NO_{3})_{2}}$)
e. Chromium(IV) Sulfate
f. Aluminum Nitrite
g. Iron(II) Phosphate
h. Sodium Hydroxide
i. Ammonium Phosphate
j. Potassium Sulfite

Part B:

a. $\ce{Ba(NO_{3})_{2}}$
b. $\ce{NH_{4}OH}$
c. $\ce{Ca_{3}(PO_{4})_{2}}$
d. $\ce{Co_{3}P_{4}}$
e. $\ce{Cr_{2}(SO_{4})_{5}}$
f. $\ce{VF_{3}}$
g. $\ce{Al(NO_{2})_{3}}$
h. $\ce{KOH}$
i. $\ce{Li_{3}PO_{4}}$
k. $\ce{CuSO_{3}}$