Target: 10 Questions in 10 minutes
An IB Chemistry data booklet is helpful |
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1. Which of the following is NOT a characteristic of an ideal gas?
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2. Which graph represents the relationship between the pressure (in Pa) and the volume (in dm3) of a fixed mass of an ideal gas at constant temperature?
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3. The deviation between real gas and ideal gas behavior is greatest at ...
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4. What will happen to the pressure of a fixed mass of gas if the temperature (in K) and the volume are both doubled?
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5. A fixed mass of a gas occupies 40cm3 at 26.85°C. At what temperature, in °C, will the volume of gas be 80cm3 if the pressure remains constant?
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6. The pressure and temperature (in K) of a fixed mass of gas are both halved. If the initial volume of the gas was 100cm3, what is the new volume?
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7. Which graph represents the relationship between the volume (in cm3) and the temperature (in °C) of a fixed mass of an ideal gas at constant pressure? | |||||||||
8. How many moles of gas are in a container of volume 2000cm3 at 100kPa pressure and a temperature of 400K? (R = 8.31 J K-1 mol-1) |
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9. A fixed mass of gas is at a pressure of 4kPa.
The volume of the gas is halved and the temperature (in K) of the gas is doubled.
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10. What is the molecular mass of gas Z if 2.00g of the gas occupies a volume of 500cm3 at 24.85°C and 1.01 x 105 Pa? (R = 8.31 J K-1 mol-1) |
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Question 1:
Let’s go through each option:
A. There is a weak attractive force between the molecules
In an ideal gas, it is assumed that there are no intermolecular forces. So weak attractive forces are not a characteristic of an ideal gas — this statement is false for an ideal gas.
B. Gas molecules occupy a negligible volume
This is true for an ideal gas (point particles).
C. Gas molecules are in random motion
This is true for an ideal gas (kinetic theory).
D. Only elastic collisions occur between molecules
This is true for an ideal gas (kinetic energy conserved in collisions).
Thus, the one that is NOT a characteristic is A.
*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.
Question 2:
The relationship between the pressure and volume of a fixed mass of an ideal gas at a constant temperature is described by Boyle's Law.
According to Boyle's Law, pressure is inversely proportional to volume. This means as the volume of the gas increases, its pressure decreases, and vice versa.
The graph that best represents this relationship is a downward-sloping curve (a hyperbola) when pressure (P) is plotted against volume (V). The equation for this relationship is PV=k, where k is a constant.
This is shown by graph A.
*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.
Question 3:
For an ideal gas, we assume:
No intermolecular forces.
Molecules have negligible volume.
Real gases deviate from ideal behavior when:
Pressure is high → molecules are forced closer together, so the volume of molecules is no longer negligible.
Temperature is low → molecules have less kinetic energy, so intermolecular attractions become significant.
Thus, the greatest deviation occurs at low temperature and high pressure.
Answer D*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.
Question 4:
We use the ideal gas law:
PV=nRTHere, n
and R are constant.Initially: P1V1=nRT1
After changes:
Volume doubled → V2=2V1
Temperature doubled (in K) → T2=2T1
New equation:
P2(2V1)=nR(2T1)But nRT1=P1V1
P2(2V1)=2(P1V1) , so:Divide both sides by 2V1 :
P2=P1So the pressure remains the same. This corresponds to answer A.
*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.
Question 5:
We can solve this using Charles’s law:
V1/T1=V2/T2where temperature is in kelvin.
Step 1: Convert given temperature to Kelvin
T1=26.85∘C+273.15=300.00 KStep 2: Solve for T2:
40/300=80/T2
So T2=80 × 300/40 = 80 × 7.5 = 600 K
Step 3: Convert T2
T2(in ∘C)=600−273.15=326.85∘C back to °CStep 4: Match with options
C: That corresponds to 326.85°C.*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.
Question 6:
We can use the combined gas law:
P1V1/T1=P2V2/T2Step 1: Identify given values
V1=100 cm3
P2=½P1
T2=½T1
V2=?
Step 2: Substitute into the equation
P1⋅100/T1= ½P1⋅V2 /½T1Step 3: Simplify the right-hand side
P1⋅100/T1= (½/½)P1⋅V2 /T1 = P1⋅V2 /T1
Step 4: Equate both sides
Cancel P1/T1from both sides:
100=V2Step 5: Conclusion
The new volume is 100 cm3. Answer B.
*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.
Question 7:
The graph that represents the relationship between the volume and the temperature in kelvin of a fixed mass of an ideal gas at constant pressure is a straight line passing through the origin of the Kelvin temperature scale.
This relationship is described by Charles's Law.
Charles's Law Explained
Charles's Law states that for a fixed mass of an ideal gas at constant pressure, the volume (V) is directly proportional to its absolute temperature (T).
Mathematically:
V∝T or V = kT
=k(where k is a constant)
If you plot Volume (y-axis) against Temperature (x-axis):
Using the Kelvin Scale (Absolute Temperature): The graph is a straight line that passes through the origin (0,0), demonstrating the direct proportionality. At 0 K, the theoretical volume of the gas is zero.
Using the Celsius Scale: The graph is still a straight line, but it does not pass through the origin. Instead, the line extrapolates (extends backward) to the x-axis (zero volume) at a temperature of −273.15 °C (Absolute Zero).
Since the question asks for the temperature in °C, the correct graph is a straight line that, when extrapolated, intersects the x-axis at −273.15 °C.
*The line will therefore be straight, but have a positive value at 0°C. This corresponds to graph C.
The Silverback (edit
)
*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.
Question 8:
We use the ideal gas law:
PV=nRTStep 1: Convert units to match R (8.31 J K⁻¹ mol⁻¹)
Pressure P=100 kPa=1.0×105 Pa
Volume V=2000 cm3= 2.0×10−3 m3
Temperature T=400 K
Step 2: Solve for n
n=PV/RTSubstitute:
n= (1.0×105)×(2.0×10−3)/ (8.31×400)Step 3: Match with given options
B: 100 x 2 is the same as our (1.0×105)×(2.0×10−3)
That’s correct.
* The Silverback (edit - removed the other options which are incorrect, for brevity)
*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.
Question 9:
We use the combined gas law:
P1V1/T1=P2V2/T2Step 1: Identify given values
P1=4 kPa
V2=½V1
T2=2T1
P2=?
Step 2: Substitute into the equation
4⋅V1/T1=P2⋅½V1/2T1Step 3: Simplify the right-hand side
P2⋅½V1/2T1= P2⋅V1/4T1So:
4⋅V1/T1=P2⋅V1/4T1Step 4: Cancel V1/T1from both sides
4=P2 / 4, so P2 = 16 (kPa)Step 5: Conclusion
The new pressure is 16 kPa
Answer D*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.
Question 10:
We use the ideal gas law:
PV=nRTwhere n=m/M, with m= mass, M = molar mass.
So:
PV=(m/M)RTStep 1: Identify given values in correct units
m=2.00 g
V=500 cm3=5.00×10-4 m3
T=24.85∘C=24.85+273.15≈298 K
P=1.01×105 Pa
R=8.31 J K−1mol−1
Step 2: Write expression for M
M=mRT / PV
M=(2.00×8.31×298) / (1.01×105×5.00×10-4)Step 3: Match with options
That matches C exactly:
M=(2.00×8.31×298) / (1.01×105×5.00×10-4)*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.