Chem Lab EXAM QUESTIONS ACCURATE AND VERIFIED ACTUAL EXAM QUESTIONS WITH DETAILED ANSWERS FOR GUARANTEED PASS | ALREADY GRADED A

What is the chemical formula for the ternary compound composed of Al³⁺ and CN⁻ ions? A) AlCN B) Al₂(CN)₃ C) Al(CN)₃ D) Al₃CN Correct Answer: C) Al(CN)₃ Rationale: Aluminum forms a +3 ion (Al³⁺), and cyanide is a -1 ion (CN⁻). Three CN⁻ ions are needed to balance one Al³⁺, giving the formula Al(CN)₃. What is the systematic name for aqueous H₃PO₃? A) Phosphoric acid B) Phosphorous acid C) Phosphide acid D) Hypophosphorous acid Correct Answer: B) Phosphorous acid Rationale: H₃PO₃ is derived from phosphorous acid, not phosphoric acid. The "-ous" suffix indicates a lower oxidation state of phosphorus. What is the systematic name for (NH₄)₂CO₃? A) Ammonium carbonite B) Ammonium carbonate C) Dinitrogen carbonate D) Ammonium bicarbonate Correct Answer: B) Ammonium carbonate Rationale: (NH₄)₂CO₃ is made from ammonium ions (NH₄⁺) and carbonate ions (CO₃²⁻). What is the Latin system name for PbI₂? A) Lead(II) iodide B) Plumbic iodide C) Plumbous iodide D) Lead(I) iodide Correct Answer: C) Plumbous iodide Rationale: Pb in PbI₂ has a +2 charge; the Latin name for lead(II) is plumbous. What is the chemical formula for sulfurous acid? A) H₂SO₄ B) H₂S C) H₂SO₃ D) HSO₄⁻ Correct Answer: C) H₂SO₃ Rationale: Sulfurous acid contains the sulfite ion (SO₃²⁻), resulting in H₂SO₃. What is the chemical formula for dinitrogen trioxide? A) N₂O₃ B) NO₂ C) NO₃ D) N₂O Correct Answer: A) N₂O₃ Rationale: The prefix “di-” means two nitrogen atoms; “tri-oxide” means three oxygen atoms. What is the chemical formula for hydrobromic acid? A) HBr B) HBrO C) HBrO₃ D) H₂Br Correct Answer: A) HBr Rationale: Hydrobromic acid is the aqueous form of hydrogen bromide, written as HBr(aq). What is the chemical formula for the oxide ion? A) O⁻ B) O₂ C) O²⁻ D) O₃ Correct Answer: C) O²⁻ Rationale: The oxide ion has a 2− charge, denoted as O²⁻. What is the chemical formula for tetraphosphorus trisulfide? A) P₄S₃ B) PS₄ C) P₃S₄ D) P₂S₃ Correct Answer: A) P₄S₃ Rationale: “Tetra-” indicates 4 phosphorus atoms and “tri-” indicates 3 sulfur atoms. What is the systematic name for NH₄Cl? A) Ammonium chloride B) Ammonium chlorate C) Nitrogen trichloride D) Hydrogen chloride Correct Answer: A) Ammonium chloride Rationale: NH₄⁺ is ammonium, and Cl⁻ is chloride, making the compound ammonium chloride. What is the systematic name for aqueous HI? A) Hypoiodous acid B) Iodic acid C) Hydroiodic acid D) Iodous acid Correct Answer: C) Hydroiodic acid Rationale: Binary acids in water are named with the “hydro-” prefix and “-ic” suffix. Aqueous H₂S is classified as which of the following? A) Ternary acid B) Binary acid C) Organic acid D) Hydroxy acid Correct Answer: B) Binary acid Rationale: H₂S contains hydrogen and a nonmetal (sulfur), making it a binary acid. What is the systematic name for aqueous H₂CO₃? A) Hydrogen carbonate B) Carbonic acid C) Bicarbonic acid D) Dihydrogen carbonate Correct Answer: B) Carbonic acid Rationale: H₂CO₃ is an oxyacid derived from the carbonate ion. The compound Na₂SO₄ is classified as which of the following? A) Binary ionic B) Ternary molecular C) Ternary ionic D) Organic compound Correct Answer: C) Ternary ionic Rationale: Na₂SO₄ contains three elements—Na, S, and O—and is ionic in nature. What is the systematic name for Cl₂O₇? A) Chlorate B) Dichlorine heptaoxide C) Chloric oxide D) Heptachlorine dioxide Correct Answer: B) Dichlorine heptaoxide Rationale: The name reflects 2 chlorine atoms (di-) and 7 oxygen atoms (hepta-). What is the systematic name for PO₄³⁻? A) Phosphite ion B) Phosphide ion C) Phosphate ion D) Tetraphosphorus ion Correct Answer: C) Phosphate ion Rationale: PO₄³⁻ is known as the phosphate ion, commonly found in fertilizers. The selenate ion SeO₃²⁻ is classified as: A) Monatomic cation B) Binary ionic compound C) Polyatomic anion D) Oxyacid Correct Answer: C) Polyatomic anion Rationale: SeO₃²⁻ consists of more than one atom and carries a negative charge. What is the chemical formula for chloric acid? A) HClO B) HClO₂ C) HClO₃ D) HClO₄ Correct Answer: C) HClO₃ Rationale: Chloric acid is derived from the chlorate ion (ClO₃⁻). What is the chemical formula for the ternary compound composed of Zn²⁺ and OH⁻ ions? A) Zn(OH) B) ZnOH₂ C) Zn₂(OH)₃ D) Zn(OH)₂ Correct Answer: D) Zn(OH)₂ Rationale: Zn²⁺ balances with two OH⁻ ions to form Zn(OH)₂. What is the systematic name for NH₄⁺? A) Ammonia B) Ammonium C) Nitrogenium D) Nitrate Correct Answer: B) Ammonium ion Rationale: NH₄⁺ is the ammonium ion, a common polyatomic cation. What is the chemical formula for the stannous ion? A) Sn⁴⁺ B) Sn²⁺ C) Sn₄ D) Sn³⁺ Correct Answer: B) Sn²⁺ Rationale: "Stannous" refers to tin(II), or Sn²⁺ in the Latin naming system. The compound Ag₂S is classified as which of the following? A) Binary molecular B) Ternary ionic C) Binary ionic D) Organic compound Correct Answer: C) Binary ionic Rationale: Ag₂S consists of silver (Ag⁺) and sulfur (S²⁻), making it a binary ionic compound. What is the systematic name for aqueous HClO? A) Chloric acid B) Hypochlorous acid C) Perchloric acid D) Chlorous acid Correct Answer: B) Hypochlorous acid Rationale: HClO is the oxyacid derived from the hypochlorite ion (ClO⁻). Predict the chemical formula for gallium sulfide, given the formula of aluminum oxide, Al₂O₃. A) GaS B) Ga₂O₃ C) Ga₂S₃ D) Ga₃S₂ Correct Answer: C) Ga₂S₃ Rationale: Like aluminum, gallium forms a +3 ion. To balance with S²⁻, the formula becomes Ga₂S₃. The H₃O⁺ ion is classified as which of the following? A) Monatomic cation B) Binary acid C) Polyatomic cation D) Neutral molecule Correct Answer: C) Polyatomic cation Rationale: H₃O⁺ (hydronium) consists of three hydrogen atoms and one oxygen atom. Which of the following acids is named: hydro + nonmetal stem + ic acid? A) H₂S(aq) B) HF(aq) C) HBr(aq) D) All of these Correct Answer: D) All of these Rationale: All are binary acids and follow the naming pattern "hydro + root + ic acid." What is the chemical formula for hydrochloric acid? A) HCl B) HClO C) HClO₃ D) HCl(aq) Correct Answer: D) HCl(aq) Rationale: Hydrochloric acid is aqueous hydrogen chloride, denoted HCl(aq). The S²⁻ ion is classified as which of the following? A) Polyatomic anion B) Cation C) Monatomic anion D) Radical Correct Answer: C) Monatomic anion Rationale: S²⁻ is a single sulfur atom with a 2− charge. What is the predicted ionic charge of an element in group 16? A) 1− B) 2+ C) 2− D) 3− Correct Answer: C) 2− Rationale: Group 16 elements tend to gain two electrons to complete their octet. What is the chemical formula for aluminum bromide? A) AlBr B) AlBr₂ C) Al₂Br₃ D) AlBr₃ Correct Answer: D) AlBr₃ Rationale: Al³⁺ requires three Br⁻ ions to balance the charge, forming AlBr₃. The hypoiodite ion, IO⁻, is classified as: A) Monatomic anion B) Polyatomic anion C) Binary ionic D) Cation Correct Answer: B) Polyatomic anion Rationale: IO⁻ consists of iodine and oxygen with an overall negative charge. What is the chemical formula for hydrocyanic acid? A) HCN B) HNC C) HCNO D) H₃CN Correct Answer: A) HCN(aq) Rationale: Hydrocyanic acid is the aqueous form of hydrogen cyanide (HCN).