Thermochemical Equations
Chemistry ⇒ Thermochemistry and Energetics
Thermochemical Equations starts at 10 and continues till grade 12.
QuestionsToday has an evolving set of questions to continuously challenge students so that their knowledge grows in Thermochemical Equations.
How you perform is determined by your score and the time you take.
When you play a quiz, your answers are evaluated in concept instead of actual words and definitions used.
See sample questions for grade 10
Describe the difference between a chemical equation and a thermochemical equation.
Describe what happens to the enthalpy change if the direction of a reaction is reversed.
Describe what is meant by the standard state of a substance in thermochemical equations.
Explain why it is important to specify the physical states of substances in a thermochemical equation.
Given the thermochemical equation: 2SO2(g) + O2(g) → 2SO3(g); ΔH = -198 kJ, what is the enthalpy change for the formation of 1 mole of SO3?
Given the thermochemical equation: C(s) + O2(g) → CO2(g); ΔH = -394 kJ, how much heat is released when 12 g of carbon is burned? (Atomic mass of C = 12)
Given the thermochemical equation: N2(g) + 3H2(g) → 2NH3(g); ΔH = -92 kJ, how much heat is released when 1 mole of NH3 is formed?
If the thermochemical equation for the combustion of hydrogen is 2H2(g) + O2(g) → 2H2O(l); ΔH = -572 kJ, what is the enthalpy change for the combustion of 4 moles of hydrogen?
Which of the following best describes an endothermic reaction? (1) Heat is released (2) Heat is absorbed (3) ΔH is negative (4) ΔH is positive
Which of the following is a correct thermochemical equation for the formation of water vapor? (1) H2(g) + 1/2O2(g) → H2O(g); ΔH = -242 kJ (2) H2(g) + O2(g) → 2H2O(g); ΔH = -484 kJ (3) 2H2(g) + O2(g) → 2H2O(g); ΔH = -484 kJ (4) H2(g) + 1/2O2(g) → H2O(l); ΔH = -286 kJ
Which of the following is always included in a thermochemical equation? (1) The physical states of reactants and products (2) The enthalpy change (ΔH) (3) The temperature at which the reaction occurs (4) The pressure of the system
Which of the following is an example of an exothermic reaction? (1) Photosynthesis (2) Combustion of propane (3) Melting of ice (4) Decomposition of calcium carbonate
Fill in the blank: If a thermochemical equation is multiplied by 2, the enthalpy change (ΔH) is also ______ by 2.
Fill in the blank: In a thermochemical equation, the enthalpy change (ΔH) is written on the ______ side of the equation if the reaction is exothermic.
Fill in the blank: The enthalpy change for a reaction is called the ______ of reaction.
Fill in the blank: The enthalpy change for a reaction is represented by the symbol ______.
State whether the following statement is true or false: The coefficients in a thermochemical equation refer to the number of moles of each substance.
True or False: Reversing a thermochemical equation changes the sign of ΔH.
True or False: The enthalpy change for a reaction is always measured under standard conditions.
True or False: The enthalpy change for a reaction is directly proportional to the amount of substance involved.
