All of the following chemical reactions are endothermic except
Correct answer: C. H2O(g) → H2O(l)
- A. H2O(s) → H2O(l)
- B. 2H2O(g) → 2H2(g) + O2(g)
- C. H2O(g) → H2O(l)
- D. Al2O3(l) + 2Fe(l) → 2Al(s) + Fe2O3(s)
Explanation
An endothermic reaction is a chemical reaction that absorbs heat from its surroundings, resulting in an increase in the internal energy of the system. Therefore, the products have more internal energy than the reactants.The phase transition from a gas to a liquid is an exothermic process. The molecules or atoms in the gas phase have sufficient kinetic energy to have overcome the attractive forces between the molecules or atoms.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? [email protected]
About Thermochemistry and Energetics of Chemical Reactions
Thermochemistry measures energy changes in chemical reactions and distinguishes exothermic from endothermic processes. Work covers systems, surroundings and state functions, internal energy, the first law of thermodynamics, enthalpy and Hess's law, including the sign conventions used when heat enters or leaves a system.
Practise Thermochemistry and Energetics of Chemical Reactions
728 free Thermochemistry and Energetics of Chemical Reactions MCQs from Chemistry, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Chemistry questions like this
Chemistry is on 14 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Thermochemistry and Energetics of Chemical Reactions questions
Ho of which of the following reactions is equal to the standard enthalpy of formation of NH3?
The melting of ice at body temperature is an endothermic process:H2O(s) _>H2O(1) ΔΗ= +6.0kJ/mo.Thus eating ice counteracts the exothermic processes of metabolizing food. How much ice (in grams) would you have to eat to counteract the energy gained by eating 28.3g of peanuts (13 kJ/g)?
Suppose you have a balloon of given volume, V1, containing a gas at Temperature, T1. When you place the balloon in a colder room at temperature, T2, the balloon's temperature starts to drop. What are the signs of the system's q, w,and E for this process?
All of the following are incorrect except
An environmental chemist got an idea that two serious pollutants (CO and NO) of the automobile exhaust can be converted to less harmful gases CO₂ and N2. The reaction is CO(g) + NO(g) CO2(g) + 2 N2(g). ΔΗ° = ?The enthalpy of this reaction as calculated from the following date isCO(g) + 1/2 O2(g)CO2(g). ΔΗ° = -283kJ/molCO(g) + O2(g) 2NO2(g). ΔΗ° = 180.6kJ/mol
A chemist heated a balloon by supplying 600 J of heat. The balloon expandsdoing 200 J of work against the atmospheric pressure. The change in internalenergy of