Molecules react with oxygen in air to provide heat, light and smoke. This reaction is
Exothermic
Endothermic
Combustion
Displacement
An example for endothermic reaction
formation of ammonia
photosynthesis
formation of SO3
formation of water
When barium hydroxide and ammonium chloride are mixed in a glass of water, the temperature of the system
falls rapidly
raises slowly
remains same
increases rapidly
Energy required to break hydrogen molecules is
105 k Cal / mol
104 k Cal / mol
103 k Cal / mol
107 k Cal / mol
The energy required to break a bond is called
bond energy
bond dissociation energy
bond dissipation
bond enthalpy
Every substance is associated with a definite amount of energy called
Bond energy
Internal energy
Enthalpy
Entropy
The energy released when a new bond is formed is called
Photosynthesis is a
exothermic reaction
endothermic reaction
decomposition
combination
The ΔH value (heat content value) for endothermic is
positive
negative
zero
one
The reactants used during photosynthesis
H2O & CO2
CO & H2O
O2 & CO2
H2O &H2
