{
  "id": "24f94e28-0c97-5ac7-aa81-315f4594dabc",
  "slug": "r1-2-energy-cycles-in-reactions-sl",
  "title": "R1.2 Energy cycles in reactions (SL)",
  "course": "IB Chemistry",
  "level": "SL",
  "syllabusCode": "R1.2",
  "questionCount": 13,
  "page": "https://splycr.com/ib-chemistry/r1-2-energy-cycles-in-reactions-sl",
  "data": "https://splycr.com/library/r1-2-energy-cycles-in-reactions-sl.json",
  "play": "https://splycr.com/?set=24f94e28-0c97-5ac7-aa81-315f4594dabc",
  "section": {
    "name": "Reactivity 1: What drives chemical reactions?",
    "page": "https://splycr.com/ib-chemistry/what-drives-chemical-reactions"
  },
  "source": {
    "name": "Biology by Bradford",
    "href": "https://www.biologybybradford.com",
    "note": "Written for the splycr library by Biology by Bradford."
  },
  "questions": [
    {
      "number": 1,
      "question": "Bond breaking is always…?",
      "answer": "Endothermic",
      "wrongOptions": [
        "Exothermic",
        "Spontaneous",
        "Reversible"
      ]
    },
    {
      "number": 2,
      "question": "Energy to break one mole of a given bond in gaseous molecules, from many compounds?",
      "answer": "Average bond enthalpy",
      "wrongOptions": [
        "Lattice enthalpy",
        "Activation energy",
        "Ionisation energy"
      ]
    },
    {
      "number": 3,
      "question": "Bond enthalpy data apply only to substances in which state?",
      "answer": "Gaseous",
      "wrongOptions": [
        "Liquid",
        "Solid",
        "Aqueous"
      ]
    },
    {
      "number": 4,
      "question": "Expression for ΔH from bond enthalpies?",
      "answer": "Σ(broken) − Σ(formed)",
      "wrongOptions": [
        "Σ(formed) − Σ(broken)",
        "Σ(broken) + Σ(formed)",
        "Σ(formed) ÷ Σ(broken)"
      ]
    },
    {
      "number": 5,
      "question": "Bond enthalpies H–H 436, Cl–Cl 242, H–Cl 431 kJ mol⁻¹: ΔH for H₂ + Cl₂ → 2HCl?",
      "answer": "−184 kJ mol⁻¹",
      "wrongOptions": [
        "+184 kJ mol⁻¹",
        "+247 kJ mol⁻¹",
        "−247 kJ mol⁻¹"
      ]
    },
    {
      "number": 6,
      "question": "CH₄(g) → C(g) + 4H(g) needs 1656 kJ mol⁻¹. Average C–H bond enthalpy?",
      "answer": "414 kJ mol⁻¹",
      "wrongOptions": [
        "1656 kJ mol⁻¹",
        "828 kJ mol⁻¹",
        "6624 kJ mol⁻¹"
      ]
    },
    {
      "number": 7,
      "question": "ΔH from bond enthalpies only approximates experiment because bond enthalpies are…?",
      "answer": "Average values",
      "wrongOptions": [
        "Exact values",
        "Liquid-phase values",
        "Entropy values"
      ]
    },
    {
      "number": 8,
      "question": "Which of these bonds has the highest bond enthalpy?",
      "answer": "C≡C",
      "wrongOptions": [
        "C=C",
        "C–C",
        "C–H"
      ]
    },
    {
      "number": 9,
      "question": "A reaction is exothermic when the bonds formed are, overall…?",
      "answer": "Stronger",
      "wrongOptions": [
        "Weaker",
        "Longer",
        "More polar"
      ]
    },
    {
      "number": 10,
      "question": "Total enthalpy change is independent of the route taken: this is…?",
      "answer": "Hess's law",
      "wrongOptions": [
        "Charles's law",
        "Avogadro's law",
        "Le Chatelier's principle"
      ]
    },
    {
      "number": 11,
      "question": "ΔH(A → B) = −100 and ΔH(B → C) = +30 kJ mol⁻¹. ΔH(A → C)?",
      "answer": "−70 kJ mol⁻¹",
      "wrongOptions": [
        "+70 kJ mol⁻¹",
        "−130 kJ mol⁻¹",
        "+130 kJ mol⁻¹"
      ]
    },
    {
      "number": 12,
      "question": "ΔH for X → Y is +50 kJ. ΔH for Y → X?",
      "answer": "−50 kJ",
      "wrongOptions": [
        "+50 kJ",
        "0 kJ",
        "−25 kJ"
      ]
    },
    {
      "number": 13,
      "question": "ΔH for A → B is −30 kJ. ΔH for 2A → 2B?",
      "answer": "−60 kJ",
      "wrongOptions": [
        "−30 kJ",
        "−15 kJ",
        "+60 kJ"
      ]
    }
  ]
}