WorksheetsSpontaneous and nonspontaneous reactions
Total questions: 10
Worksheet time: 5mins
What is a spontaneous process in chemistry?
A process that requires external intervention process that requires external intervention
A process that occurs without outside intervention
A process that always absorbs energy
A process that is always exothermic
Which of the following is an example of a spontaneous process?
Boiling water in a kettle
Charging a battery
Rusting of iron
Mixing sugar in water
Some spontaneous processes (combustion reactions) require what type of energy from the surroundings?
Electrical energy
Thermal energy
Kinetic energy
Magnetic energy
In the chemical equation 2Fe2O3 (s) → 4Fe (s) + 3O2 (g) AH=+1625 kJ , what is the change in enthalpy (ΔH) for the reverse form of this reaction?
a) -1625 kJ
b) +1625 kJ
c) 0 kJ
d) -325 kJ
What happens to the sign of ΔH when you reverse the direction of a chemical reaction?
a) It stays the same
b) Changes to the opposite sign
c) It becomes positive
d) It becomes zero
Is the formation of rust on iron an exothermic or endothermic reaction?
a) Exothermic
b) Endothermic
Which of the following reactions is both spontaneous and exothermic?
a) Photosynthesis
b) Combustion of gasoline
c) Melting ice
d) Dissolving salt in water
What factor primarily determines the spontaneity of a chemical reaction?
a) Temperature
b) Pressure
c) ΔH (enthalpy change)
d) Concentration of reactants
Which process requires an external energy source to proceed?
a) Freezing water
b) Boiling water
c) Condensing water vapor
How can the knowledge of spontaneity and energy changes in chemistry be applied in everyday life (e.g.: Iron rusting)?
a) By making coffee
b) By predicting weather patterns
c) By controlling chemical reactions for various purposes
d) By charging a smartphone
