Calculate the oxidation number of each atom in the following: CrO₄²⁻, NO₃⁻, CaO, Zn, H₂O, Sr²⁺

How do oxidation numbers of each element of the following reactions change?

1. Ag(s) + CN^-(aq) + O₂(g) → Ag(CN)₂^-(aq) + H₂O(l)

2. NaI(aq) + 3HOCl(aq) → NaIO₃(aq) + 3HCl(aq).

Which statement is true for the following reaction?

CH₄ (g) + 2 O₂ (g) → CO₂ (g) + 2 H₂O (l)

Identify element being reduced and element being oxidized in the following reaction:

1. Cl₂ (aq) + 2NaI (aq) → I₂ (aq) + 2NaCl (aq)

2. 3 Fe(NO₃)₂ (aq) + 2 AI (s) → 3 Fe (s) + 2 AI(NO ₃)₃ (aq)

Label the following as a non-redox or redox reaction. Determine the reducing agent and the oxidizing agent for the identified redox reaction.

I. Mg (s) +Cl₂ (g) → MgCl₂ (s)

II. Cu (s) + 2 Ag⁺ (aq) → Cu²⁺ (aq) + Ag (s)

III. 2 K (s) + F₂ (g) → 2 KF (s)

IV. N₂O₃ (g) + H₂O (l) → HNO₂ (aq)

A 0.350 g sample of a certain semimetal M heated in air yielded the matching oxide M₂O₃. The reaction needed 7.67 mL of 0.125 M  Cr₂O₇²⁻  when the oxide was dissolved in aqueous acid and titrated with K₂Cr₂O₇. The unbalanced equation for the titration is H₃MO₃(aq) + Cr₂O₇²⁻(aq) → H₃MO₄(aq) + Cr³⁺(aq) (in acid).

How many moles of semimetal were present in the initial 0.350 g sample and how many moles of oxide were formed?

A sample contains palladium, cadmium, and other impurities. The mass percent of palladium and cadmium can be determined using a process that starts with the sample being dissolved in hot nitric acid. Aqueous ammonia is used to lessen the acidity of the resulting solution of Cu²⁺ and Pd²⁺ ions, and then sodium thiocyanate (NaSCN) and sulfuric acid (H₂SO₄) are added to precipitate palladium thiocyanate (PdSCN). The collected solid PdSCN is dissolved in water, treated with potassium iodate (KIO₃) to produce iodine, and then titrated with aqueous sodium thiosulfate (Na₂S₂O₃). After PdSCN is removed, the filtrate is neutralized by adding aqueous ammonia. Then, a solution of diammonium hydrogen phosphate ((NH₄)₂HPO₄) is added, resulting in a precipitate of cadmium ammonium phosphate (CdNH₄PO₄). The precipitate is transformed into cadmium pyrophosphate (Cd₂P₂O₇) by heating it to 900 °C, which is then weighed. The equations involved in the process are: 

(1) Pd(s) + NO₃^—(aq) → Pd⁴⁺(aq) + NO(g) (in acid)

(2) Pd⁴⁺(aq) + SCN^—(aq) + HSO₃^—(aq) → Pd(SCN)₂(s) + HSO₄^—(aq) (in acid)

(3) Pd²⁺(aq) + IO₃^—(aq) → Pd⁴⁺(aq) + I₂(aq) (in acid)

(4) I₂(aq) + S₂O₃^2—(aq) → I^—(aq) + S₄O₆^2—(aq) (in acid)

(5) CdNH₄PO₄(s) → Cd₂P₂O₇(s) + H₂O(g) + NH₃(g)

Give the balance equation for each reaction.

Give the balanced equation for the following half-reactions occurring in an acidic solution.

Balance the following redox reaction under basic conditions and identify the oxidizing and reducing agents:

CrO₂^-(aq) + S₂O₈^2-(aq) → CrO₄^2-(aq) + SO₄^2-(aq)

Balance the following reduction-oxidation reaction in basic solution. What is the coefficient in front of OH^-?

Br_2(l) → BrO₃^-_(aq) + Br^-_(aq)

You are provided the following reagents: antimony, platinum, nickel, aqueous copper(II) chloride solution, and hydrochloric acid solution. Assuming the reaction undergoes in an Erlenmeyer flask with a balloon attached to it, which combination of reagents would you use to obtain a chemical reaction that will fill up the balloon? Determine the identity of the gas that fills up the ballon.

The following half-reactions are arranged from most reactive to least reactive.

Br₂ (l) + e^–→ 2 Br^– (aq)

Cu⁺ (aq) + e^– → Cu (s)

Mo³⁺ (aq) + 3 e^– → Mo(s)

Li⁺ (aq) + e^– → Li (s)

i) Identify the strongest oxidizing agent

ii) Identify the strongest reducing agent?

iii) Will the following reaction proceed?  Mo³⁺ (aq) + Cu (s) → Mo(s) + Cu⁺ (aq)