Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

1. Consider the reaction when aqueous solutions of iron(III) sulfate and ammoniu

ID: 1005558 • Letter: 1

Question

1. Consider the reaction when aqueous solutions of iron(III) sulfate and ammonium carbonate are combined.

Find the net ionic equation for this reaction, along with states of matter.

2. Write the net ionic equation for the following molecular equation. Along with states of matter.

3. Consider the reaction when aqueous solutions of calcium nitrate and ammonium phosphate are combined. Find net ionic equation and states of matter.

4. Write a net ionic equation for the overall reaction that occurs when aqueous solutions of phosphoric acid and sodium hydroxide are combined. Assume excess base, include states of matter.

5. Write a net ionic equation for the reaction that occurs when sodium sulfite (aq) and excess hydroiodic acid are combined. Include states of matter. Note: Sulfites follow the same solubility trends as sulfates.

6. Determine the oxidation state for each of the elements below.

The oxidation state of

silicon

in

silicate ion
SiO32-

is

.

The oxidation state of

chlorine

in

chlorine pentafluoride
ClF5

is

.

The oxidation state of

boron

in

metaboric acid
HBO2

is

.

The oxidation state of

...

silicon

...

in

...

silicate ion
SiO32-

...

is

...

.

The oxidation state of

chlorine

in

chlorine pentafluoride
ClF5

is

.

The oxidation state of

boron

in

metaboric acid
HBO2

is

.

7. Identify the species oxidized, the species reduced, the oxidizing agent and the reducing agent in the following electron transfer reaction.
Hg2+ + MgHg + Mg2+

As the reaction proceeds, electrons are transferred from where to where.

Explanation / Answer

There is difference between Complete ionic equations and net ionic equations.

Following steps are needed to write net ionic equation from complete ionic equation.

1. We have to write the balanced molecular equation, including the state of each substance.

2. Write the ionic equation, showing which compound dissociated in ions.

3. Cancel out the spectator ions that appear on both sides of the equation to get the net ionic equation.

1. Molecular - Fe2(SO4)3(aq) + 3(NH4)2CO3(aq) = 3(NH4)2SO4(aq) + Fe2(CO3)3(s)

Complete ionic –

Fe2+(aq) + 3(SO4)2-(aq) + 6NH4+(aq) + 3CO3 2-(aq) = 6NH4+(aq) + 3(SO4)2-(aq) + Fe2+(aq) + 3CO3 2-(aq)

Net ionic reaction – No reaction

2. 3CaI2(aq) + 2K3PO4(aq) = Ca3(PO4)2(s) + 6KI(aq)

Complete ionic –

3Ca+2(aq) + 6I-(aq) + 6K+(aq) + 2PO4 3-(aq) = Ca3(PO4)2(s) + 6K+(aq) + 6I-(aq)

Net ionic reaction – 3Ca+2(aq) + 2PO4 3-(aq) = Ca3(PO4)2(s)

3. 3Ca(NO3)2(aq) + 2(NH4)3PO4 (aq) = Ca3(PO4)2 (s) + 6(NH4)(NO3)

3Ca+2(aq) + 3NO3 2-(aq) + 6NH4+(aq) + 2PO4 3-(aq) = Ca3(PO4)2 (s) + 6NH4+(aq) + 6NO3 2-(aq)

Net ionic reaction – 3Ca+2(aq) + 2PO4 3-(aq) = Ca3(PO4)2(s)

4. H3PO4(aq) + 3NaOH(aq) = Na3PO4(aq) + 3H2O(aq)

3H+(aq) + PO4 2-(aq) + 3Na+(aq) + 3OH-(aq) = 3Na+(aq) + PO4 2-(aq) + 3H2O(aq)

In acid base reactions net ionic reaction is always H+ + OH- = H2O

5. Na2S (aq) + 2 HCl (aq) = H2S (g) + 2 NaCl (aq)

2Na+(aq) + S2-(aq) + 2H+(aq) + 2Cl-(aq) = H2S(g) + 2Na+(aq) + 2Cl-(aq)

S2-(aq) + 2H+(aq) = H2S (g)

6. Oxidation state of silicon in SiO3 2-

Charge on SiO3 is -2.

Consider oxidation state of Si as n. Oxidation state of oxygen is -2

n + 3(-2) = -2

n = +4

Oxidation state of silicon in SiO3 2- is +4

Oxidation state of Cl in ClF5

Sum of oxidation state should always be zero in neutral compounds.

Charge on F is -1

n + 5(-1) = 0

n = 5

Oxidation state of Chlorine in ClF5 is +5

HBO2

Oxidation state of O is -2 and that of H is +1

+1 + n + 2(-2) = 0

n = +3

Oxidation state of Boron in HBO2 is +3.

7.

Hg2+ + Mg = Hg + Mg2+

Oxidation is loss of electrons and reduction is gain of electrons. Oxidizing agent reduces itself to oxidize another one. Also the reducing agent oxidizes itself to reduce another one.

Hg2+ + 2e- ---> Hg (gain of electron) Reduction

Mg ------> Mg2+ + 2e- (loss of electron) oxidization

Mg is reducing agent and Hg is oxidizing agent.