Practice Structure 3. Classification of matter with authentic IB Chemistry exam questions for both SL and HL students. This question bank mirrors Paper 1A, 1B, 2 structure, covering key topics like atomic structure, chemical reactions, and organic chemistry. Get instant solutions, detailed explanations, and build exam confidence with questions in the style of IB examiners.
A research team investigates the chemical behavior of Period 3 oxides to understand their industrial and environmental applications. The team analyzes the following oxides: , , and .
Classify the type of bonding in each of the following oxides and relate it to their position in Period 3:
Describe the trend in acid–base character of the oxides across Period 3 from sodium to chlorine.
Predict whether reacts with both acids and bases, and justify your answer using acid–base theory.
Group 1 metals react vigorously with water.
Write a balanced chemical equation for the reaction of lithium with water.
Compare the reactivity of lithium and potassium with water.
Explain the trend in reactivity of Group 1 elements down the group using atomic structure.
A student is analyzing samples of different organic compounds in a school laboratory to identify their functional groups, which determine their chemical properties.
Define the term functional group in the context of organic chemistry.
Identify the functional group present in alcohols.
Name the functional group present in carboxylic acids and draw its displayed structure.
The following infrared spectrum is for 2-butanone, an organic compound with the molecular formula .
Identify the functional group present in 2-butanone that corresponds to the strong absorption peak around 1715 .
Predict why there is no broad absorption peak in the region around 3200–3600 .
Discuss the significance of multiple sharp peaks appear between 1000-1300 in organic structure identification.
The IR spectrum of 2-butanone was recorded to monitor a chemical reaction.
Explain how this spectrum could be used to determine whether 2-butanol has been fully oxidized to 2-butanone.
2-butanone and butanoic acid have the same molecular formula.
Describe how their IR spectra would differ, and explain how these differences arise.
The compound benzophenone contains two phenyl (benzene) rings bonded to a central carbonyl () group.
State the molecular formula of benzophenone.
Identify the functional group present in benzophenone.
Benzophenone is insoluble in water but soluble in organic solvents.
Explain this difference in terms of intermolecular forces.
Urea is a small organic molecule excreted in the urine of mammals. It plays an important role in the removal of excess nitrogen from the body.
The structure of urea is shown below:
Identify the functional group present in urea.
Deduce the molecular formula of urea.
Write a balanced chemical equation for the formation of urea from ammonia and carbon dioxide.
Explain why urea is highly soluble in water. Refer to relevant intermolecular forces.
A student dissolves 6.00 g of urea in 100.0 g of water.
Calculate the amount of substance (in mol) of urea dissolved. (Molar mass = 60.06 )
Urea can form hydrogen bonds with water.
Draw a Lewis structure of urea and clearly indicate one possible hydrogen bond between urea and a water molecule.
The structure of ethenone () is shown below:
State the empirical formula and the molecular formula of ethenone.
Identify the types of bonds present between the atoms in ethenone.
Ethenone is classified as a compound with two functional groups.
Identify the two functional groups present in the molecule.
Ethenone is a reactive molecule.
Predict its polarity based on molecular geometry and electronegativity.
Only one enantiomer of a chiral drug may have the desired biological effect.
Explain what is meant by the term chiral carbon.
State how many stereoisomers exist for a compound with two chiral centers.
Explain how enantiomers interact with plane-polarized light.
Electron configurations reveal periodic patterns.
State the number of valence electrons in an atom of oxygen.
Deduce the electron configuration of phosphorus ().
Explain how the group number relates to the number of valence electrons.
The graph of first ionization energy across Period 3 shows small irregularities.
Define first ionization energy.
Explain the general trend in first ionization energy across Period 3.
Account for the lower ionization energy of aluminum compared to magnesium, despite the overall trend.
Explain why sulfur also has a slightly lower first ionization energy than phosphorus.