WorksheetsMajor Review SI Session
Total questions: 21
Worksheet time: 16mins
Is the following process exothermic or endothermic: Molten aluminum solidifies
endothermic
exothermic
Is the following process exothermic or endothermic:
Rubbing alcohol evaporates from the skin
endothermic
exothermic
Why is the ΔH negative for an exothermic process?
(a)
The internal energy of a system is always increased by
having the system do work on the surroundings
adding heat to the system and having the system do work on the surroundings
adding heat to the system
withdrawing heat from the system
Which one of the following conditions would always result in increase in the internal energy of a system?
The system gains heat and has work done on it by the surroundings
The system loses heat and does work on the surroundings
The system gains heat and does work on the surroundings
None of the above is correct
Of the following, which one is a state function?
heat
H
w
q
Which compound should have the largest magnitude in lattice energy
KF
SrI2
MgO
NaI
Which statement is FALSE?
Energy is neither created nor destroyed, excluding nuclear reactions
Exothermic reaction gives off heat to the surroundings
Endothermic reactions have positive ΔH values
State functions depend on the path taken to arrive at a particular state
Calculate ΔE for the combustion of a gas that releases 210.0 kJ of heat to its surroundings and does 65.5 kJ of work on its surroundings
(a)
Arrange the following ionic compounds in order of increasing magnitude of lattice energy
MgO, NaCl, MgCl2, CaO
NaCl<MgCl2<MgO<CaO
MgO<CaO<MgCl2<NaCl
NaCl<CaO<MgCl2<MgO
NaCl<MgCl2<CaO<MgO
What does a negative sign for ΔS indicate?
The system is becoming more ordered
The system is becoming less ordered
What is a spontaneous reaction?
A reaction that occurs without ongoing outside intervention
A reaction that occurs fast without ongoing outside intervention
A reaction that requires outside intervention to proceed
All the above
A spontaneous change leads to _______
disorder
order
I don't know
What is entropy (ΔS) ?
the thermodynamic state function that describes the amount of disorder
The thermodynamic state function that describes the amount of order
A large value for entropy means a high degree of (a)
Which has higher entropy?
1 mol of CO2 (s) or 1 mol of CO2 (g)
1 mol of CO2 (s)
1 mol of CO2 (g)
Which has a higher entropy?
Seawater in Midwinter at 2 degrees Celsius or in summer at 23 degrees Celsius
Seawater at 2 Degrees Celsius
Seawater at 23 degrees Celsius
Predict whether entropy will increases or decreases going from reactants to products:
N2(g) + 3H2 (g) -> 2NH3 (g)
Increase
Decrease
In order for a change to occur spontaneously ΔSuniv must be
greater than 0
less than 0
equal to 0
In order for a spontaneous reaction to occur, ΔG must be
greater than 0
less than 0
equal to 0
If ΔHsys is exothermic and ΔSsys is positive, this means ΔG is negative and reaction is _________ at all temperatures
spontaneous
nonspontaneous
