Question
Use the table to answer the question.
Bonds and Bond Energies for Given Reactions
Reaction Bonds Present Energy of Bonds Broken and Formed (kJ/mol)
C + O2→CO2
O=O
2 C=O
499
1478
N2+O2→2NO
N≡N
O=O
2 N=O
946
499
1214
S+O2→SO2
O=O
2 S=O
499
1044
2CO+O2→2CO2
2 C≡O
O=O
4 C=O
2148
499
2956
Which reaction is endothermic?
(1 point)
Responses
N2+O2→2NO
N sub 2 plus O sub 2 rightarrow 2 N O
S+O2→SO2
S plus O sub 2 rightarrow S O sub 2
C + O2→CO2
C plus O sub 2 rightarrow C O sub 2
2CO+O2→2CO2
Bonds and Bond Energies for Given Reactions
Reaction Bonds Present Energy of Bonds Broken and Formed (kJ/mol)
C + O2→CO2
O=O
2 C=O
499
1478
N2+O2→2NO
N≡N
O=O
2 N=O
946
499
1214
S+O2→SO2
O=O
2 S=O
499
1044
2CO+O2→2CO2
2 C≡O
O=O
4 C=O
2148
499
2956
Which reaction is endothermic?
(1 point)
Responses
N2+O2→2NO
N sub 2 plus O sub 2 rightarrow 2 N O
S+O2→SO2
S plus O sub 2 rightarrow S O sub 2
C + O2→CO2
C plus O sub 2 rightarrow C O sub 2
2CO+O2→2CO2
Answers
GPT-4o mini
To determine which reaction is endothermic, we need to look at the energy changes involved in each reaction. A reaction is endothermic if the energy of the products is greater than the energy of the reactants, leading to a net absorption of energy. We do this by breaking down the total energies of the bonds broken and formed during each reaction.
Let's analyze each reaction using the provided bond energies:
1. **C + O₂ → CO₂**
- Bonds broken: O=O (499 kJ)
- Bonds formed: 2 C=O (2 × 799 kJ = 1598 kJ)
- Net energy change: 499 (broken) - 1598 (formed) = -1099 kJ (exothermic)
2. **N₂ + O₂ → 2NO**
- Bonds broken: N≡N (946 kJ) + O=O (499 kJ) = 1445 kJ
- Bonds formed: 2 N=O (2 × 946 kJ = 1892 kJ)
- Net energy change: 1445 (broken) - 1892 (formed) = -447 kJ (exothermic)
3. **S + O₂ → SO₂**
- Bonds broken: O=O (499 kJ)
- Bonds formed: 2 S=O (2 × 522 kJ = 1044 kJ)
- Net energy change: 499 (broken) - 1044 (formed) = -545 kJ (exothermic)
4. **2CO + O₂ → 2CO₂**
- Bonds broken: 2 C≡O (2 × 1072 kJ = 2144 kJ) + O=O (499 kJ) = 2643 kJ
- Bonds formed: 4 C=O (4 × 799 kJ = 3196 kJ)
- Net energy change: 2643 (broken) - 3196 (formed) = -553 kJ (exothermic)
From our analysis above, all the given reactions are exothermic, which means they release energy. However, since the question asks for which reaction is endothermic, we conclude that none of these reactions are endothermic based on the information in the table provided. All reactions release energy instead.
Let's analyze each reaction using the provided bond energies:
1. **C + O₂ → CO₂**
- Bonds broken: O=O (499 kJ)
- Bonds formed: 2 C=O (2 × 799 kJ = 1598 kJ)
- Net energy change: 499 (broken) - 1598 (formed) = -1099 kJ (exothermic)
2. **N₂ + O₂ → 2NO**
- Bonds broken: N≡N (946 kJ) + O=O (499 kJ) = 1445 kJ
- Bonds formed: 2 N=O (2 × 946 kJ = 1892 kJ)
- Net energy change: 1445 (broken) - 1892 (formed) = -447 kJ (exothermic)
3. **S + O₂ → SO₂**
- Bonds broken: O=O (499 kJ)
- Bonds formed: 2 S=O (2 × 522 kJ = 1044 kJ)
- Net energy change: 499 (broken) - 1044 (formed) = -545 kJ (exothermic)
4. **2CO + O₂ → 2CO₂**
- Bonds broken: 2 C≡O (2 × 1072 kJ = 2144 kJ) + O=O (499 kJ) = 2643 kJ
- Bonds formed: 4 C=O (4 × 799 kJ = 3196 kJ)
- Net energy change: 2643 (broken) - 3196 (formed) = -553 kJ (exothermic)
From our analysis above, all the given reactions are exothermic, which means they release energy. However, since the question asks for which reaction is endothermic, we conclude that none of these reactions are endothermic based on the information in the table provided. All reactions release energy instead.