The thermal decomposition of calcium carbonate is an example of:
An exothermic reaction.
An endothermic reaction.
A neutralisation reaction.
Burning a fuel such as coal or natural gas is an example of:
Using the following bond energies, calculate the energy change for the reaction below.
2H2 + O2 -> 2H2O
H-H 436 kJ , O=O 498 kJ , O-H 463 kJ
+490 kJ
- 482 kJ
+482 kJ
Which statement is correct?
A reaction is exothermic if more energy is needed to break the bonds in the reactants than is given out when the bonds in the products form.
A reaction is exothermic if more energy is needed to break the bonds in the reactants than is needed when the bonds in the products form.
A reaction is endothermic if more energy is needed to break the bonds in the reactants than is given out when the bonds in the products form.
Bond making takes in energy and bond breaking releases energy.
Bond breaking takes in energy and bond making releases energy.
Bond making takes in energy and bond breaking takes in energy.
CH4 + 2O2 -> CO2 + 2H2O
C-H 412 kJ , O=O 498 kJ , O-H 463 kJ , C=O 743 kJ
-694 kJ
-296 kJ
-541 kJ
C + O=O -> O=C=O
C=O 743 kJ, O=O 498 kJ
+245 kJ
-245 kJ
-988 kJ
In an exothermic reaction profile diagram, the:
Reactants are at a higher energy level than the products.
Products are at a higher energy level than the reactants.
Reactants and products are at the same energy level.
In an endothermic reaction profile diagram, the
Which of the following statements is true?
In a reaction profile diagram, the activation energy is the difference in energy between reactants and products.
A catalyst provides an alternative reaction pathway of lower activation energy.
In a reaction profile diagram, the activation energy is the difference in energy between products and reactants.