Measuring Energy Changes
Hesssssss Law
Bond Enthalpies
Energy Cycles
Entropy and Spontaneity
100
Heat travels from a hotter to a colder medium (True or False)
True
100
∆H3 = ∆H2 + ∆H1, ∆H1 = ?
∆H3-∆H2
100
bond enthalpy
energy required to break one mole of chemical bonds in the gaseous state.
100
Born-Haber cycle
Born–Haber cycle is an energy cycle that can be used to calculate the lattice enthalpy of an ionic compound.
100
Entropy
Distribution of available energy among particles in a system
200
A system's temperature lowers (exo or endo)
exothermic
200
What is Carbon's enthalpy of formation in graphite?
0 zero null J
200
Bond making is...
Exothermic
200
1/2 Cl2(g)--->Cl(g)
Enthalpy of Atomization
200
Explain
Gibbs free energy being negative means an energy is spontaneous
300
The sign of ΔH in an exothermic reaction
negative
300
Hess' Law
Hess’s law states that the total enthalpy change in a chemical reaction is independent of the route by which the chemical reaction takes place, as long as the initial and final conditions are the same.
300
More energy in bond forming than breaking means
energy is released
300
Hydration Energy
1 mole of gaseous ions dissolves in sufficient water to give an infinitely dilute solution
300
Physical State with highest entropy value
Gas
400
Calorimetry is used to measure what and how does it work?
Measures enthalpy change, sufficient explanation
400
Enthalpy change of combustion
The enthalpy change when one mole of a substance is completely combusted in oxygen under standard conditions (298 K and 100 kPa)
400
The energy required of Oxygen gas O2 to break is more or less than the energy required to break Ozone O3
More, as there is a strong covalent bond present.
400
The size of a lattice enthalpy depends on
Size of the ions and charge carried
400
If ∆H is positive, ∆S is negative, is the reaction spontaneous or not?
not