For a fixed mass of gas at a constant temperature, what happens to the volume if the pressure of the gas is doubled?

:br
::indent
- A.$\hspace{1em}$Volume will remain the same

- B.$\hspace{1em}$Volume will double

- C.$\hspace{1em}$Volume will be halved

- D.$\hspace{1em}$Volume will increase exponentially

Which of the following conditions makes gases deviate from ideal behavior?

::indent
- A.$\hspace{1em}$ High pressure and high temperature

- B.$\hspace{1em}$ Low pressure and low temperature

- C.$\hspace{1em}$ High pressure and low temperature

- D.$\hspace{1em}$ Low pressure and high temperature

Based on the graph below, choose the correct statement that describes the relationship between pressure and temperature for a fixed mass and volume of a gas?

:::center
![1.3-36](question:02187be4-3809-445d-b70e-4ae6dde3de0d)
:::

::indent
- A.$\hspace{1em}$Pressure is inversely proportional to the absolute temperature

- B.$\hspace{1em}$Pressure is directly proportional to the square of the absolute temperature

- C.$\hspace{1em}$Pressure is inversely proportional to the square of the absolute temperature

- D.$\hspace{1em}$Pressure is directly proportional to the absolute temperature

\[Maximum mark: 8\]

The ideal gas equation is a formula that combines the relationship between pressure, volume, temperature, and the number of moles.

1. Complete the table below by calculating the missing variables of the ideal gas equation. :marks[4]

:::center
| $\mathbf{P}$         | $\mathbf{V}$            | $\mathbf{n}$         | $\mathbf{T}$        |
| :-:        | :-:           | :-:       | :-:      |
| (1)        | $\quad 0.015\, m^{3}\quad$ | $0.400\, mol$ | $37 ^\circ \mathrm{C}$    |
| $\quad 152,000\, Pa\quad$ | (2)           | $2.00\, mol$  | $\quad 298.15\, K\quad$ |
| $31,000\, Pa$  | $0.25\, m^{3}$  | (3)       | $271.15\, K$ |
| $250\,kPa$     | $0.75\, dm^{3}$ | $\quad 0.580\, mol\quad$ | (4)      |
:::

2. A $256\, cm^{3}$ flask contains $0.800\, g$ of a gaseous compound with an empirical formula of CHCl. The pressure and the temperature of the gas are respectively $10^{5}\, Pa$ and $373\, K$. Determine the molecular formula of the compound. :marks[4]

\[Maximum mark: 4\]

Liquid butanol, C$_4$H$_9$OH(l), burns or combusts in oxygen to produce $\ce{CO_2}$(g) and $\ce{H_2O}$(g).



1. Write a balanced equation, including state symbols, for this reaction. :marks[1]

2. When 1.250 cm$^3$ of butanol is combusted in excess oxygen, 1.921 dm$^3$ of water vapor is collected at a pressure of 125.0 kPa and 150.0$^\circ$C. Calculate the moles of butanol that were combusted. :marks[2]

3. Determine the density of liquid butanol in g cm$^{-3}$. :marks[1]

Based on the table below, what is the correct calculation to determine the final volume of a fixed mass of gas:

:br

:::center
| |Initial|Final|
| :-:        | :-:                  | :-:                  |
| Pressure (atm)      |1.00 | 1.60|
| Temperature ($^\circ$C)     | 20 | 10|
| Volume (dm$^3$)  | 5.00        | ? |
:::

:br

::indent
- A.$\hspace{1em}$ $\dfrac{(1.00 \ \textrm{atm})(5.00 \  \textrm{dm}^3)(283 \ \textrm{K})}{(1.60\ \textrm{atm})(293\ \textrm{K})}$

- B.$\hspace{1em}$ $\dfrac{(1.00 \textrm{\ atm})(5.00 \ \textrm{dm}^3)(10 \ ^\circ\mathrm{C})}{(1.60 \textrm{\ atm})(20 \  ^\circ\mathrm{C})}$

- C.$\hspace{1em}$ $\dfrac{(1.60 \textrm{\ atm})(5.00\ \textrm{dm}^3)(20 ^\circ\mathrm{C})}{(1.00 \textrm{\ atm})(10 ^\circ\mathrm{C})}$

- D.$\hspace{1em}$ $\dfrac{(1.60 \textrm{\ atm})(5.00\ \textrm{dm}^3)(283\textrm{\ K})}{(1.00 \textrm{\ atm})(293\textrm{\ K})}$

Under which conditions would a gas deviate the most from the ideal gas model?
:br
::indent 
- A.$\hspace{1em}$1 $atm$, 298 $K$

- B.$\hspace{1em}$200 $atm$, 298 $K$
- C.$\hspace{1em}$2 $atm$, 25 $^\circ$C
- D.$\hspace{1em}$100 $kPa$, 25 $^\circ$C





\[Maximum mark: 3\]

Automobile airbags are inflated with $\ce{N2}$, a byproduct of sodium azide decomposition, according to the following reaction.

:::center
$\ce{2 NaN_{3(s)} -> 2 Na_{(s)} + 3 N_{2(g)}}$
:::

Calculate the mass (in grams) of sodium azide needed to generate $0.07 \,$m$^{3}$ of $\ce{N2}$ at $1.01 \times 10^{5} \,$Pa and $26.0 ^\circ$C.

$14.01\,g$ of nitrogen gas ($\ce{N2}$) is reacted with excess $\ce{H2}$. What volume of ammonia ($\ce{NH3}$) gas would be produced at STP? The molar volume of a gas at STP is $22.7 \,dm^3$.

:::center
$\ce{N2(g) + 3H2(g) -> 2NH3(g)}$
:::

::indent
- A.$\hspace{1em}$ $11.4\, dm^3$

- B.$\hspace{1em}$ $22.7\, dm^3$

- C.$\hspace{1em}$ $34.1\, dm^3$

- D.$\hspace{1em}$ $45.4\, dm^3$

\[Maximum mark: 5\]

Sodium azide is an ionic compound found within the airbags of some older cars. The airbag is deployed as a safety feature in the event of an accident. In this application, the sodium azide decomposes rapidly, and the gas formed inflates the airbag.

The decomposition of sodium azide under these conditions is given below.

:::center
$\ce{2NaN3(s)-> 2Na(s) + 3N2(g)}$
:::

1. Suggest the formula and charge for the azide ion. :marks[1]

2. A typical airbag requires $65.0\, dm^{3}$ of nitrogen gas for complete inflation at STP. Using section $2$ of the data booklet, calculate the mass of sodium azide that the airbag must contain for this purpose. :marks[4]

Which of the following gases most closely aligns with the behavior of an ideal gas?
:br
::indent
- A.$\hspace{1em}$ $\ce{Br2}$, bromine

- B.$\hspace{1em}$ $\ce{H2}$, hydrogen
- C.$\hspace{1em}$ $\ce{Cl2}$, chlorine
- D.$\hspace{1em}$ $\ce{O2}$, oxygen

 


The rate of formation of $\ce{CH3OH}$ over the first 5 minutes at standard temperature and pressure is ${4.0\ g\ min^{-1}}$. 

What volume of $\ce{H2}$ in $cm^3$ has reacted after 3 minutes (molar gas volume at STP = $22.7\ dm^3\ mol^{-1}$)?

:::center
$\ce{CO_{(g)} + 2H_{2(g)} \rightarrow CH3OH_{(l)}}$
:::

:br

::indent
- A. $\hspace{1em}$ $\dfrac{12.0\ \times\ 22.7\ \times\ 10^3}{2\ \times\ (12.01\ +\ 4.04\ +\ 16.00)}$

- B. $\hspace{1em}$ $\dfrac{12.0\ \times\ 2\ \times\ 22.7\ \times\ 10^3}{\ (12.01\ +\ 4.04\ +\ 16.00)}$
- C. $\hspace{1em}$ $\dfrac{12.0\ \times\ 22.7\ \times\ 10^3}{\ (12.01\ +\ 4.04\ +\ 16.00)}$
- D. $\hspace{1em}$ $\dfrac{12.0\ \times\ 22.7\ \times\ 2}{\ (12.01\ +\ 4.04\ +\ 16.00)}$


Ideal Gases, Real Gases' Deviation, Molar Volume, Ideal Gas Equation, Combined Gas Law

SL - 2025

Models of the Particulate Nature of Matter

Introduction To The Particulate Nature Of Matter

CH0850

CH0851

CH0852

CH0853

CH0014

CH0854

The Nuclear Atom

CH0048

CH0047

CH0050

CH0679

CH0017

CH0057

CH0056

Electron Configurations

CH0262

CH0258

CH0397

CH0589

CH0253

CH0266

CH0685

CH0684

The Mole

CH0022

CH0371

CH0026

CH0027

CH0028

Ideal Gases

CH0963

CH0964

CH0965

CH0043

CH0070

Elements, Compounds, Mixtures, Separation Techniques, Kinetic Molecular Theory, Changes of States

Introduction to the Particulate Nature of Matter

CH0001

CH0010

CH0006

CH0007

CH0013

CH1103

CH1093

CH1094

CH1096

CH1098

CH1099

CH1100

CH1101

CH1102

CH1104

CH1105

Atomic Structure, Subatomic Particles, Isotopes, Atomic Number, Mass Number

CH0049

CH0052

CH0051

CH0678

CH0055

CH0054

Hydrogen Emission Spectra, Wavelength, Frequency, Energy, Full & Condensed Electron Configuration, Orbital Diagram

CH0255

CH0254

CH0259

CH0261

CH0267

CH0268

CH0257

CH0264

CH0686

CH0263

CH0775

CH0779

CH0256

CH0260

CH0813

CH0265

CH0583

CH0690

CH0398

Moles, Mass, Molar Mass, Relative Atomic Mass, Relative Formula Mass, Empirical vs Molecular Formulas, Avogadro's Law 

CH0015

CH0019

CH0018

CH0016

CH0020

CH0031

CH0021

CH0025

CH0236

CH0249

CH1335

CH0032

CH0034

CH0036

CH0041

CH0673

CH0033

CH0035

CH0844

Models of Bonding & Structure

The Ionic Model

CH0159

CH0700

CH0062

CH0064

CH0008

CH0966

The Covalent Model

CH0347

CH0339

CH0788

CH0953

CH0586

CH0281

CH0711

The Metallic Model

CH0536

CH0535

CH0538

CH0539

CH0713

CH0545

From Models to Materials

CH0147

CH0540

CH0541

CH0960

CH0958

CH0961

CH0962

Ionic Bond, Ionic Compounds, Polyatomic Ions

CH0058

CH0067

CH0061

CH0060

CH0003

CH0284

CH0291

CH0063

CH0066

CH0294

Covalent & Coordination Bonds, Octet Rule, Lewis Formula, VSEPR, Bond & Molecular Polarities, IMF, Chromatography

CH0342

CH0282

CH0283

CH0286

CH0274

CH0315

CH0278

CH0344

CH0279

CH0345

CH0293

CH0275

CH0273

CH0288

CH0350

CH0287

CH0346

CH0277

CH0295

CH0702

CH0338

CH0280

CH0271

CH0343

CH0269

CH0140

CH0285

CH1033

CH0954

CH0645

CH0957

CH0951

CH0004

Metallic Bond (Definition & Strength), Metals (Conductivity, Malleability, Melting Points Trend)

CH0543

CH0534

CH0533

CH0546

Bonding & Properties of a Material, Bonding Triangle, Alloys, Natural & Synthetic Polymers, Polymerization Reactions

IB Chemistry SL - 2025 - Questionbank

S1.5 - Ideal Gases

Question 1

Question 2

Question 3

Question 4

Question 5

Question 6

Question 7

Question 8

Question 9

Question 10

Question 11

Question 12

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