Which table can be used to tell whether a reaction is exothermic or endothermic? How can we tell?
Table I. If Delta H is positive, reaction is endothermic. If Delta H is negative, the reaction is exothermic.
100
Thermal Energy is kinetic energy, potential energy, both or neither?
Kinetic
200
What is kinetic energy?
Energy of motion
200
What is activation energy?
The energy that is needed to start a chemical reaction
200
C2H5OH(l) + 3O2(g) → 2CO2(g) + 3H2O(l)
Exothermic
200
An object that has kinetic energy must be?
In motion
300
What form of energy is associated with the random motion of the particles in a sample of water?
Thermal Energy
300
In terms of energy, temperature is also referred to as the measure of _____________?
Temperature is the measure of the average kinetic energy of particles in a sample of matter.
300
C6H12O6(s) +6O2(g) → 6CO2(g) + 6H2O(l)
Exothermic
300
Given the balanced equation:
I + I → I2
Is a bond formed or broken? Will energy be released or absorbed.
A bond is formed and energy is released.
400
What is chemical energy?
Energy that is stored in the bonds of chemical compounds.
Energy that is available for release from chemical reactions.
400
The burning of magnesium involves a conversion of
(1) chemical energy to mechanical energy
(2) chemical energy to heat energy
(3) heat energy to chemical energy
(4) heat energy to mechanical energy
(2) chemical energy to heat energy
400
N2(g) + 2O2(g) → 2NO2(g)
Endothermic
400
As the height increases, so does?
Potential energy
500
What is Electrical energy?
Electrical energy is energy caused by the movement of electrons
500
Which of the following is a conversion from chemical energy to thermal energy?
(1) Coal is burned to boil water
(2) Food is digested and used to regulate body temperature
(3) Charcoal is burned in a barbecue pit
(4) All of the above
(4) All of the above
500
What type of reaction is there when going form a solid to a gas? How about from gas to a solid?
solid → liquid → gas = endothermic reaction
gas → liquid → solid = exothermic reaction
500
Energy cannot be ____(1)____ or _____(2)_____ we can only ____(3)____ energy.